Fresh Fish 8/FreshFishVol8-CD1.bin/gnu/info/fileutils.info

GNU Info File | 1994-12-22 | 101KB | 1,999 lines

This is Info file fileutils.info, produced by Makeinfo-1.55 from the
input file fileutils.texi.
START-INFO-DIR-ENTRY
* File utilities: (fileutils).  GNU file utilities.
* chgrp: (fileutils)chgrp invocation.            Change file groups.
* chown: (fileutils)chown invocation.            Change file owners/groups.
* chmod: (fileutils)chmod invocation.            Change file permissions.
* cp: (fileutils)cp invocation.                    Copy files.
* dd: (fileutils)dd invocation.                    Copy and convert a file.
* df: (fileutils)df invocation.                    Report filesystem disk usage.
* dir: (fileutils)dir invocation.        List directories briefly.
* du: (fileutils)du invocation.                    Report on disk usage.
* install: (fileutils)install invocation.    Copy and change attributes.
* ln: (fileutils)ln invocation.                    Make links between files.
* ls: (fileutils)ls invocation.            List directory contents.
* mkdir: (fileutils)mkdir invocation.            Create directories.
* mkfifo: (fileutils)mkfifo invocation.            Create FIFOs: (named pipes).
* mknod: (fileutils)mknod invocation.            Create special files.
* mv: (fileutils)mv invocation.                    Rename files.
* rm: (fileutils)rm invocation.                    Remove files.
* rmdir: (fileutils)rmdir invocation.            Remove empty directories.
* sync: (fileutils)sync invocation.            Synchronize memory and disk.
* touch: (fileutils)touch invocation.            Change file timestamps.
* vdir: (fileutils)vdir invocation.        List directories verbosely.
END-INFO-DIR-ENTRY
   This file documents the GNU set of file utilities.
   Copyright (C) 1994 Free Software Foundation, Inc.
   Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.
   Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided that
the entire resulting derived work is distributed under the terms of a
permission notice identical to this one.
   Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions, except that this permission notice may be stated in a
translation approved by the Foundation.
File: fileutils.info,  Node: Top,  Next: Introduction,  Prev: (DIR),  Up: (DIR)
GNU file utilities
******************
   This manual minimally documents version GNU fileutils 3.12 of the
GNU file utilities.
* Menu:
* Introduction::        Caveats, overview, and authors.
* Common options::              Common options.
* File permissions::        Access modes.
* Directory listing::           ls dir vdir d v
* Basic operations::            cp dd install mv rm
* Special file types::          ln mkdir rmdir mkfifo mknod
* Changing file attributes::    chgrp chmod chown touch
* Disk usage::                  df du sync
* Index::                       General index.
File: fileutils.info,  Node: Introduction,  Next: Common options,  Prev: Top,  Up: Top
Introduction
************
   This manual is incomplete: No attempt is made to explain basic file
concepts in a way suitable for novices.  Thus, if you are interested,
please get involved in improving this manual.  The entire GNU community
will benefit.
   The GNU file utilities are mostly compatible with the POSIX.2
standard.
   Please report bugs to `[e-mail]'.  Remember to
include the version number, machine architecture, input files, and any
other information needed to reproduce the bug.  *Note Bugs: (gcc)Bugs.
   This manual is based on the Unix man pages in the distribution, which
were originally written by David MacKenzie and updated by Jim Meyering.
Franc,ois Pinard did the initial conversion to Texinfo format.  Karl
Berry did the indexing, some reorganization, and editing of the results.
Richard Stallman contributed his usual invaluable insights to the
overall process.
File: fileutils.info,  Node: Common options,  Next: File permissions,  Prev: Introduction,  Up: Top
Common options
**************
   Certain options are available in all these programs.  Rather than
writing identical descriptions for each of the programs, they are
described here.  (In fact, every GNU program accepts (or should accept)
these options.)
`--help'
     Print a usage message listing all available options, then exit
     successfully.
`--version'
     Print the version number, then exit successfully.
* Menu:
* Backup options::              -b -S -V, in some programs.
File: fileutils.info,  Node: Backup options,  Up: Common options
Backup options
==============
   Some GNU programs (at least `cp', `mv', and `ln') optionally make
backups of files before writing new versions.  These options control
the details of these backups.  The options are also briefly mentioned
in the descriptions of the particular programs.
`--backup'
     Make backups of files that are about to be overwritten or removed.
     Without this option, the original versions are destroyed.
`-S SUFFIX'
`--suffix=SUFFIX'
     Append SUFFIX to each backup file made with `-b'.  If this option
     is not specified, the value of the `SIMPLE_BACKUP_SUFFIX'
     environment variable is used.  And if `SIMPLE_BACKUP_SUFFIX' is not
     set, the default is `~', just as in Emacs.
`-V METHOD'
`--version-control=METHOD'
     Use METHOD to determine the type of backups made with `-b'.  If
     this option is not specified, the value of the `VERSION_CONTROL'
     environment variable is used.  And if `VERSION_CONTROL' is not set,
     the default backup type is `existing'.
     This option corresponds to the Emacs variable `version-control';
     the same values for METHOD are accepted as in Emacs.  This options
     also more descriptive name.  The valid METHODs (unique
     abbreviations are accepted):
    `t'
    `numbered'
          Always make numbered backups.
    `nil'
    `existing'
          Make numbered backups of files that already have them, simple
          backups of the others.
    `never'
    `simple'
          Always make simple backups.
File: fileutils.info,  Node: File permissions,  Next: Directory listing,  Prev: Common options,  Up: Top
File permissions
****************
   Each file has a set of "permissions" that control the kinds of
access that users have to that file.  The permissions for a file are
also called its "access mode".  They can be represented either in
symbolic form or as an octal number.
* Menu:
* Mode Structure::              Structure of file permissions.
* Symbolic Modes::              Mnemonic permissions representation.
* Numeric Modes::               Permissions as octal numbers.
File: fileutils.info,  Node: Mode Structure,  Next: Symbolic Modes,  Up: File permissions
Structure of File Permissions
=============================
   There are three kinds of permissions that a user can have for a file:
  1. permission to read the file.  For directories, this means
     permission to list the contents of the directory.
  2. permission to write to (change) the file.  For directories, this
     means permission to create and remove files in the directory.
  3. permission to execute the file (run it as a program).  For
     directories, this means permission to access files in the
     directory.
   There are three categories of users who may have different
permissions to perform any of the above operations on a file:
  1. the file's owner;
  2. other users who are in the file's group;
  3. everyone else.
   Files are given an owner and group when they are created.  Usually
the owner is the current user and the group is the group of the
directory the file is in, but this varies with the operating system, the
filesystem the file is created on, and the way the file is created.  You
can change the owner and group of a file by using the `chown' and
`chgrp' commands.
   In addition to the three sets of three permissions listed above, a
file's permissions have three special components, which affect only
executable files (programs) and, on some systems, directories:
  1. set the process's effective user ID to that of the file upon
     execution (called the "setuid bit").  No effect on directories.
  2. set the process's effective group ID to that of the file upon
     execution (called the "setgid bit").  For directories on some
     systems, put files created in the directory into the same group as
     the directory, no matter what group the user who creates them is
     in.
  3. save the program's text image on the swap device so it will load
     more quickly when run (called the "sticky bit").  For directories
     on some systems, prevent users from removing files that they do
     not own in the directory; this is called making the directory
     "append-only".
File: fileutils.info,  Node: Symbolic Modes,  Next: Numeric Modes,  Prev: Mode Structure,  Up: File permissions
Symbolic Modes
==============
   "Symbolic modes" represent changes to files' permissions as
operations on single-character symbols.  They allow you to modify either
all or selected parts of files' permissions, optionally based on their
previous values, and perhaps on the current `umask' as well (*note
Umask and Protection::.).
   The format of symbolic modes is:
     [ugoa...][[+-=][rwxXstugo...]...][,...]
   The following sections describe the operators and other details of
symbolic modes.
* Menu:
* Setting Permissions::          Basic operations on permissions.
* Copying Permissions::          Copying existing permissions.
* Changing Special Permissions:: Special permissions.
* Conditional Executability::    Conditionally affecting executability.
* Multiple Changes::             Making multiple changes.
* Umask and Protection::              The effect of the umask.
File: fileutils.info,  Node: Setting Permissions,  Next: Copying Permissions,  Up: Symbolic Modes
Setting Permissions
-------------------
   The basic symbolic operations on a file's permissions are adding,
removing, and setting the permission that certain users have to read,
write, and execute the file.  These operations have the following
format:
     USERS OPERATION PERMISSIONS
The spaces between the three parts above are shown for readability only;
symbolic modes can not contain spaces.
   The USERS part tells which users' access to the file is changed.  It
consists of one or more of the following letters (or it can be empty;
*note Umask and Protection::., for a description of what happens then).
When more than one of these letters is given, the order that they are
in does not matter.
     the user who owns the file;
     other users who are in the file's group;
     all other users;
     all users; the same as `ugo'.
   The OPERATION part tells how to change the affected users' access to
the file, and is one of the following symbols:
     to add the PERMISSIONS to whatever permissions the USERS already
     have for the file;
     to remove the PERMISSIONS from whatever permissions the USERS
     already have for the file;
     to make the PERMISSIONS the only permissions that the USERS have
     for the file.
   The PERMISSIONS part tells what kind of access to the file should be
changed; it is zero or more of the following letters.  As with the
USERS part, the order does not matter when more than one letter is
given.  Omitting the PERMISSIONS part is useful only with the `='
operation, where it gives the specified USERS no access at all to the
file.
     the permission the USERS have to read the file;
     the permission the USERS have to write to the file;
     the permission the USERS have to execute the file.
   For example, to give everyone permission to read and write a file,
but not to execute it, use:
     a=rw
   To remove write permission for from all users other than the file's
owner, use:
     go-w
The above command does not affect the access that the owner of the file
has to it, nor does it affect whether other users can read or execute
the file.
   To give everyone except a file's owner no permission to do anything
with that file, use the mode below.  Other users could still remove the
file, if they have write permission on the directory it is in.
     go=
Another way to specify the same thing is:
     og-rxw
File: fileutils.info,  Node: Copying Permissions,  Next: Changing Special Permissions,  Prev: Setting Permissions,  Up: Symbolic Modes
Copying Existing Permissions
----------------------------
   You can base part of a file's permissions on part of its existing
permissions.  To do this, instead of using `r', `w', or `x' after the
operator, you use the letter `u', `g', or `o'.  For example, the mode
     o+g
adds the permissions for users who are in a file's group to the
permissions that other users have for the file.  Thus, if the file
started out as mode 664 (`rw-rw-r--'), the above mode would change it
to mode 666 (`rw-rw-rw-').  If the file had started out as mode 741
(`rwxr----x'), the above mode would change it to mode 745
(`rwxr--r-x').  The `-' and `=' operations work analogously.
File: fileutils.info,  Node: Changing Special Permissions,  Next: Conditional Executability,  Prev: Copying Permissions,  Up: Symbolic Modes
Changing Special Permissions
----------------------------
   In addition to changing a file's read, write, and execute
permissions, you can change its special permissions.  *Note Mode
Structure::, for a summary of these permissions.
   To change a file's permission to set the user ID on execution, use
`u' in the USERS part of the symbolic mode and `s' in the PERMISSIONS
part.
   To change a file's permission to set the group ID on execution, use
`g' in the USERS part of the symbolic mode and `s' in the PERMISSIONS
part.
   To change a file's permission to stay permanently on the swap device,
use `o' in the USERS part of the symbolic mode and `t' in the
PERMISSIONS part.
   For example, to add set user ID permission to a program, you can use
the mode:
     u+s
   To remove both set user ID and set group ID permission from it, you
can use the mode:
     ug-s
   To cause a program to be saved on the swap device, you can use the
mode:
     o+t
   Remember that the special permissions only affect files that are
executable, plus, on some systems, directories (on which they have
different meanings; *note Mode Structure::.).  Using `a' in the USERS
part of a symbolic mode does not cause the special permissions to be
affected; thus,
     a+s
has *no effect*.  You must use `u', `g', and `o' explicitly to affect
the special permissions.  Also, the combinations `u+t', `g+t', and
`o+s' have no effect.
   The `=' operator is not very useful with special permissions; for
example, the mode:
     o=t
does cause the file to be saved on the swap device, but it also removes
all read, write, and execute permissions that users not in the file's
group might have had for it.
File: fileutils.info,  Node: Conditional Executability,  Next: Multiple Changes,  Prev: Changing Special Permissions,  Up: Symbolic Modes
Conditional Executability
-------------------------
   There is one more special type of symbolic permission: if you use
`X' instead of `x', execute permission is affected only if the file
already had execute permission or is a directory.  It affects
directories' execute permission even if they did not initially have any
execute permissions set.
   For example, this mode:
     a+X
gives all users permission to execute files (or search directories) if
anyone could before.
File: fileutils.info,  Node: Multiple Changes,  Next: Umask and Protection,  Prev: Conditional Executability,  Up: Symbolic Modes
Making Multiple Changes
-----------------------
   The format of symbolic modes is actually more complex than described
above (*note Setting Permissions::.).  It provides two ways to make
multiple changes to files' permissions.
   The first way is to specify multiple OPERATION and PERMISSIONS parts
after a USERS part in the symbolic mode.
   For example, the mode:
     og+rX-w
gives users other than the owner of the file read permission and, if it
is a directory or if someone already had execute permission to it,
gives them execute permission; and it also denies them write permission
to it file.  It does not affect the permission that the owner of the
file has for it.  The above mode is equivalent to the two modes:
     og+rX
     og-w
   The second way to make multiple changes is to specify more than one
simple symbolic mode, separated by commas.  For example, the mode:
     a+r,go-w
gives everyone permission to read the file and removes write permission
on it for all users except its owner.  Another example:
     u=rwx,g=rx,o=
sets all of the non-special permissions for the file explicitly.  (It
gives users who are not in the file's group no permission at all for
   The two methods can be combined.  The mode:
     a+r,g+x-w
gives all users permission to read the file, and gives users who are in
the file's group permission to execute it, as well, but not permission
to write to it.  The above mode could be written in several different
ways; another is:
     u+r,g+rx,o+r,g-w
File: fileutils.info,  Node: Umask and Protection,  Prev: Multiple Changes,  Up: Symbolic Modes
The Umask and Protection
------------------------
   If the USERS part of a symbolic mode is omitted, it defaults to `a'
(affect all users), except that any permissions that are *set* in the
system variable `umask' are *not affected*.  The value of `umask' can
be set using the `umask' command.  Its default value varies from system
to system.
   Omitting the USERS part of a symbolic mode is generally not useful
with operations other than `+'.  It is useful with `+' because it
allows you to use `umask' as an easily customizable protection against
giving away more permission to files than you intended to.
   As an example, if `umask' has the value 2, which removes write
permission for users who are not in the file's group, then the mode:
     +w
adds permission to write to the file to its owner and to other users who
are in the file's group, but *not* to other users.  In contrast, the
mode:
     a+w
ignores `umask', and *does* give write permission for the file to all
users.
File: fileutils.info,  Node: Numeric Modes,  Prev: Symbolic Modes,  Up: File permissions
Numeric Modes
=============
   File permissions are stored internally as 16 bit integers.  As an
alternative to giving a symbolic mode, you can give an octal (base 8)
number that corresponds to the internal representation of the new mode.
This number is always interpreted in octal; you do not have to add a
leading 0, as you do in C.  Mode 0055 is the same as mode 55.
   A numeric mode is usually shorter than the corresponding symbolic
mode, but it is limited in that it can not take into account a file's
previous permissions; it can only set them absolutely.
   The permissions granted to the user, to other users in the file's
group, and to other users not in the file's group are each stored as
three bits, which are represented as one octal digit.  The three special
permissions are also each stored as one bit, and they are as a group
represented as another octal digit.  Here is how the bits are arranged
in the 16 bit integer, starting with the lowest valued bit:
     Value in  Corresponding
     Mode      Permission

               Other users not in the file's group:
        1      Execute
        2      Write
        4      Read

               Other users in the file's group:
       10      Execute
       20      Write
       40      Read

               The file's owner:
      100      Execute
      200      Write
      400      Read

               Special permissions:
     1000      Save text image on swap device
     2000      Set group ID on execution
     4000      Set user ID on execution
   For example, numeric mode 4755 corresponds to symbolic mode
`u=rwxs,go=rx', and numeric mode 664 corresponds to symbolic mode
`ug=rw,o=r'.  Numeric mode 0 corresponds to symbolic mode `ugo='.
File: fileutils.info,  Node: Directory listing,  Next: Basic operations,  Prev: File permissions,  Up: Top
Directory listing
*****************
   This chapter describes the `ls' command and its variants `dir' and
`vdir', which list information about files.
* Menu:
* ls invocation::               List directory contents.
* dir invocation::              Briefly ls.
* vdir invocation::             Verbosely ls.
File: fileutils.info,  Node: ls invocation,  Next: dir invocation,  Up: Directory listing
`ls': List directory contents
=============================
   The `ls' program lists information about files (of any type,
including directories).  Options and file arguments can be intermixed
arbitrarily, as usual.
   For non-option command-line arguments that are directories, by
default `ls' lists the contents of directories, not recursively, and
omitting files with names beginning with `.'.  For other non-option
arguments, by default `ls' lists just the filename.  If no non-option
arguments are specified, `ls' lists the contents of the current
directory.
   By default, the output is sorted alphabetically.  If standard output
is a terminal, the output is in columns (sorted vertically); otherwise,
they are listed one per line.
   Because `ls' is such a fundamental program, it has accumulated many
options over the years.  They are described in the subsections below;
within each section, options are listed alphabetically (ignoring case).
The division of options into the subsections is not absolute, since some
options affect more than one aspect of `ls''s operation.
   Also, the `-g' option is accepted but ignored, for compatibility
with Unix.  Also see *Note Common options::.
* Menu:
* Which files are listed::
* What information is listed::
* Sorting the output::
* General output formatting::
* Formatting the filenames::
File: fileutils.info,  Node: Which files are listed,  Next: What information is listed,  Up: ls invocation
Which files are listed
----------------------
   These options determine which files `ls' lists information for.  By
default, any files and the contents of any directories on the command
line are shown.
`--all'
     List all files in directories, including files that start with `.'.
`--almost-all'
     List all files in directories except for `.' and `..'.
`--ignore-backups'
     Do not list files that end with `~', unless they are given on the
     command line.
`--directory'
     List just the names of directories, as with other types of files,
     rather than listing their contents.
`--ignore'
     Do not list files whose names match the shell pattern (not regular
     expression) PATTERN unless they are given on the command line.  As
     in the shell, an initial `.' in a filename does not match a
     wildcard at the start of PATTERN.
`--dereference'
     List the files linked to by symbolic links instead of listing the
     contents of the links.
`--recursive'
     List the contents of all directories recursively.
File: fileutils.info,  Node: What information is listed,  Next: Sorting the output,  Prev: Which files are listed,  Up: ls invocation
What information is listed
--------------------------
   These options affect the information that `ls' displays.  By
default, only filenames are shown.
`--dired'
     With the long listing (`-l') format, print an additional line after
     the main output:
          //DIRED// BEG1 END1 BEG2 END2 ...
     The BEGN and ENDN are unsigned integers which record the byte
     position of the beginning and end of each filename in the output.
     This makes it easy for Emacs to find the names, even when they
     contain unusual characters such as space or newline, without fancy
     searching.
     If directories are being listed recursively (`-R'), output a
     similar line after each subdirectory:
          //SUBDIRED// BEG1 END1 ...
`--no-group'
     Inhibit display of group information in a long format directory
     listing.  (This is the default in some non-GNU versions of `ls',
     so we provide this option for compatibility.)
`--inode'
     Print the inode number (also called the file serial number and
     index number) of each file to the left of the filename.  (This
     number uniquely identifies each file within a particular
     filesystem.)
`--format=long'
`--format=verbose'
     In addition to the name of each file, print the file type,
     permissions, number of hard links, owner name, group name, size in
     bytes, and timestamp (by default, the modification time).  For
     files with a time more than 6 months old or more than 1 hour into
     the future, the timestamp contains the year instead of the time of
     day.
     For each directory that is listed, preface the files with a line
     `total BLOCKS', where BLOCKS is the total disk space used by all
     files in that directory.  By default, 1024-byte blocks are used;
     if the environment variable `POSIXLY_CORRECT' is set, 512-byte
     blocks are used (unless the `-k' option is given).  The BLOCKS
     computed counts each hard link separately; this is arguably a bug.
     This output format is the default for the GNU `v' and `vdir'
     programs.
`--size'
     Print the size of each file in 1024-byte blocks to the left of the
     filename.  If the environment variable `POSIXLY_CORRECT' is set,
     512-byte blocks are used instead, unless the `-k' option is given
     (*note General output formatting::.).
     For files that are NFS-mounted from an HP-UX system to a BSD
     system, this option reports sizes that are half the correct
     values.  On HP-UX systems, it reports sizes that are twice the
     correct values for files that are NFS-mounted from BSD systems.
     This is due to a flaw in HP-UX; it also affects the HP-UX `ls'
     program.
File: fileutils.info,  Node: Sorting the output,  Next: General output formatting,  Prev: What information is listed,  Up: ls invocation
Sorting the output
------------------
   These options change the order in which `ls' sorts the information
it outputs.  By default, sorting is done by character code (e.g., ASCII
order).
`--time=ctime'
`--time=status'
     Sort according to the status change time (the `ctime' in the
     inode).  If the long listing format (`-l') is being used, print the
     status change time instead of the modification time.
     Primarily, like `-U'--do not sort; list the files in whatever
     order they are stored in the directory.  But also enable `-a' (list
     all files) and disable `-l' and `-s' (if they were specified
     before the `-f').
`--reverse'
     Reverse whatever the sorting method is--e.g., list files in reverse
     alphabetical order, youngest first, smallest first, or whatever.
`--sort=size'
     Sort by file size, largest first.
`--sort=time'
     Sort by modification time (the `mtime' in the inode), newest first.
`--time=atime'
`--time=access'
`--time=use'
     Sort by access time (the `atime' in the inode).  If the long
     listing format is being used, print the last access time.
`--sort=none'
     Do not sort; list the files in whatever order they are stored in
     the directory.  (Do not do any of the other unrelated things that
     `-f' does.)  This is especially useful when listing very large
     directories, since not doing any sorting can be noticeably faster.
`--sort=extension'
     Sort directory contents alphabetically by file extension
     (characters after the last `.'); files with no extension are
     sorted first.
File: fileutils.info,  Node: General output formatting,  Next: Formatting the filenames,  Prev: Sorting the output,  Up: ls invocation
General output formatting
-------------------------
   These options affect the appearance of the overall output.
`--format=single-column'
     List one file per line.  This is the default for `ls' when standard
     output is not a terminal.
`--format=vertical'
     List files in columns, sorted vertically.  This is the default for
     `ls' if standard output is a terminal.  It is always the default
     for the `dir' and `d' programs.
`--classify'
     Append a character to each filename indicating the file type.
     Also, for regular files that are executable, append `*'.  The file
     type indicators are `/' for directories, `@' for symbolic links,
     `|' for FIFOs, `=' for sockets, and nothing for regular files.
`--full-time'
     List times in full, rather than using the standard abbreviation
     heuristics.  The format is the same as `date''s default; it's not
     possible to change this, but you can extract out the date string
     with `cut' and then pass the result to `date -d'.  *Note `date'
     invocation: (sh-utils)date invocation.
     This is most useful because the time output includes the seconds.
     (Unix filesystems store file timestamps only to the nearest
     second, so this option shows all the information there is.)  For
     example, this can help when you have a Makefile that is not
     regenerating files properly.
`--kilobytes'
     If file sizes are being listed, print them in kilobytes.  This
     overrides the environment variable `POSIXLY_CORRECT'.
`--format=commas'
     List files horizontally, with as many as will fit on each line,
     separated by `, ' (a comma and a space).
`--numeric-uid-gid'
     List the numeric UID and GID instead of the names.
     Append a character to each filename indicating the file type. This
     is like `-F', except that executables are not marked.
`--format=across'
`--format=horizontal'
     List the files in columns, sorted horizontally.
`--tabsize=COLS'
     Assume that each tabstop is COLS columns wide.  The default is 8.
     `ls' uses tabs where possible in the output, for efficiency.
`--width=COLS'
     Assume the screen is COLS columns wide.  The default is taken from
     the terminal settings if possible; otherwise the environment
     variable `COLUMNS' is used if it is set; otherwise the default is
     80.
File: fileutils.info,  Node: Formatting the filenames,  Prev: General output formatting,  Up: ls invocation
Formatting the filenames
------------------------
   These options change how filenames themselves are printed.
`--escape'
     Quote nongraphic characters in filenames using alphabetic and octal
     backslash sequences like those used in C.
`--literal'
     Do not quote filenames.
`--hide-control-chars'
     Print question marks instead of nongraphic characters in filenames.
     This is the default.
`--quote-name'
     Enclose filenames in double quotes and quote nongraphic characters
     as in C.
File: fileutils.info,  Node: dir invocation,  Next: vdir invocation,  Prev: ls invocation,  Up: Directory listing
`dir': Briefly list directory contents
======================================
   The `dir' program (also installed as `d') is equivalent to `ls -C';
that is, files are by default always listed in columns, sorted
vertically.
   *Note `ls': ls invocation.
File: fileutils.info,  Node: vdir invocation,  Prev: dir invocation,  Up: Directory listing
`vdir': Verbosely list directory contents
=========================================
   The `vdir' program (also installed `v')is equivalent to `ls -l';
that is, files are by default listed in long format.
File: fileutils.info,  Node: Basic operations,  Next: Special file types,  Prev: Directory listing,  Up: Top
Basic operations
****************
   This chapter describes the commands for basic file manipulation:
copying, moving (renaming), and deleting (removing).
* Menu:
* cp invocation::               Copy files.
* dd invocation::               Convert and copy a file.
* install invocation::          Copy files and set attributes.
* mv invocation::               Move (rename) files.
* rm invocation::               Remove files or directories.
File: fileutils.info,  Node: cp invocation,  Next: dd invocation,  Up: Basic operations
`cp': Copy files and directories
================================
   `cp' copies files (or, optionally, directories).  The copy is
completely independent of the original.  You can either copy one file to
another, or copy arbitrarily many files to a destination directory.
Synopsis:
     cp [OPTION]... SOURCE DEST
     cp [OPTION]... SOURCE... DIRECTORY
   If the last argument names an existing directory, `cp' copies each
SOURCE file into that directory (retaining the same name).  Otherwise,
if only two files are given, it copies the first onto the second.  It
is an error if the last argument is not a directory and more than two
non-option arguments are given.
   If the source file contains holes, `cp' copies them and other blocks
of zero bytes as holes.  Otherwise, files are written just as they are
read.  (A "hole" is a sequence of zero bytes that does not occupy any
physical disk blocks; the `read' system call reads these as zeroes.)
   By default, `cp' does not copy directories.  It also refuses to copy
a file onto itself.
   The program accepts the following options.  Also see *Note Common
options::.
`--archive'
     Preserve as much as possible of the structure and attributes of the
     original files in the copy.  Equivalent to `-dpR'.
`--backup'
     Make backups of files that are about to be overwritten or removed.
     *Note Backup options::.
`--no-dereference'
     Copy symbolic links as symbolic links rather than copying the
     files that they point to, and preserve hard links between source
     files in the copies.
`--force'
     Remove existing destination files.
`--interactive'
     Prompt whether to overwrite existing regular destination files.
`--link'
     Make hard links instead of copies of non-directories.
`--preserve'
     Preserve the original files' owner, group, permissions, and
     timestamps.
`--parents'
     Form the name of each destination file by appending to the target
     directory a slash and the specified name of the source file.  The
     last argument given to `cp' must be the name of an existing
     directory.  For example, the command:
          cp --parents a/b/c existing_dir
     copies the file `a/b/c' to `existing_dir/a/b/c', creating any
     missing intermediate directories.
     Copy directories recursively, copying any non-directories and
     non-symbolic links (that is, FIFOs and special files) as if they
     were regular files.  This means trying to read the data in each
     source file and writing it to the destination.  Thus, with this
     option, `cp' may well hang indefinitely reading a FIFO, unless
     something else happens to be writing it.
`--recursive'
     Copy directories recursively, preserving non-directories (see `-r'
     just above).
`--symbolic-link'
     Make symbolic links instead of copies of non-directories.  All
     source filenames must be absolute (starting with `/') unless the
     destination files are in the current directory.  This option merely
     results in an error message on systems that do not support
     symbolic links.
`-S SUFFIX'
`--suffix=SUFFIX'
     Append SUFFIX to each backup file made with `-b'.  *Note Backup
     options::.
`--update'
     Do not copy a nondirectory that has an existing destination with
     the same or newer modification time.
`--verbose'
     Print the name of each file before copying it.
`-V METHOD'
`--version-control=METHOD'
     Change the type of backups made with `-b'.  The METHOD argument
     can be `numbered' (or `t'), `existing' (or `nil'), or `never' (or
     `simple').  *Note Backup options::.
`--one-file-system'
     Skip subdirectories that are on different filesystems from the one
     that the copy started on.
File: fileutils.info,  Node: dd invocation,  Next: install invocation,  Prev: cp invocation,  Up: Basic operations
`dd': Convert and copy a file
=============================
   `dd' copies a file (from standard input to standard output, by
default) with a changeable I/O blocksize, while optionally performing
conversions on it.  Synopsis:
     dd [OPTION]...
   The program accepts the following options.  Also see *Note Common
options::.
   The numeric-valued options below (BYTES and BLOCKS) can be followed
by a multiplier: `b'=512, `c'=1, `k'=1024, `w'=2, `xM'=M.
`if=FILE'
     Read from FILE instead of standard input.
`of=FILE'
     Write to FILE instead of standard output.  Unless `conv=notrunc'
     is given, `dd' truncates FILE to zero bytes (or the size specified
     with `seek=').
`ibs=BYTES'
     Read BYTES bytes at a time.
`obs=BYTES'
     Write BYTES bytes at a time.
`bs=BYTES'
     Both read and write BYTES bytes at a time.  This overrides `ibs'
     and `obs'.
`cbs=BYTES'
     Convert BYTES bytes at a time.
`skip=BLOCKS'
     Skip BLOCKS `ibs'-byte blocks in the input file before copying.
`seek=BLOCKS'
     Skip BLOCKS `obs'-byte blocks in the output file before copying.
`count=BLOCKS'
     Copy BLOCKS `obs'-byte blocks from the input file, instead of
     everything until the end of the file.
`conv=CONVERSION[,CONVERSION]...'
     Convert the file as specified by the CONVERSION argument(s).  (No
     spaces around any comma(s).)
     Conversions:
    `ascii'
          Convert EBCDIC to ASCII.
    `ebcdic'
          Convert ASCII to EBCDIC.
    `ibm'
          Convert ASCII to alternate EBCDIC.
    `block'
          For each line in the input, output `cbs' bytes, replacing the
          input newline with a space and padding with spaces as
          necessary.
    `unblock'
          Replace trailing spaces in each `cbs'-sized input block with a
          newline.
    `lcase'
          Change uppercase letters to lowercase.
    `ucase'
          Change lowercase letters to uppercase.
    `swab'
          Swap every pair of input bytes.  GNU `dd', unlike others,
          works when an odd number of bytes are read--the last byte is
          simply copied (since there is nothing to swap it with).
    `noerror'
          Continue after read errors.
    `notrunc'
          Do not truncate the output file.
    `sync'
          Pad every input block to size of `ibs' with trailing zero
          bytes.
File: fileutils.info,  Node: install invocation,  Next: mv invocation,  Prev: dd invocation,  Up: Basic operations
`install': Copy files and set attributes
========================================
   `install' copies files while setting their permission modes and, if
possible, their owner and group.  Synopses:
     install [OPTION]... SOURCE DEST
     install [OPTION]... SOURCE... DIRECTORY
     install -d [OPTION]... DIRECTORY...
   In the first of these, the SOURCE file is copied to the DEST target
file.  In the second, each of the SOURCE files are copied to the
destination DIRECTORY.  In the last, each DIRECTORY (and any missing
parent directories) is created.
   `install' is similar to `cp', but allows you to control the
attributes of destination files.  It is typically used in Makefiles to
copy programs into their destination directories.  It refuses to copy
files onto themselves.
   The program accepts the following options.  Also see *Note Common
options::.
     Ignored; for compatibility with old Unix versions of `install'.
`--directory'
     Create each given directory and any missing parent directories,
     setting the owner, group and mode as given on the command line or
     to the defaults.  It also gives any parent directories it creates
     those attributes.  (This is different from the SunOS 4.x
     `install', which gives directories that it creates the default
     attributes.)
`-g GROUP'
`--group=GROUP'
     Set the group ownership of installed files or directories to
     GROUP. The default is the process's current group.  GROUP may be
     either a group name or a numeric group id.
`-m MODE'
`--mode=MODE'
     Set the permissions for the installed file or directory to MODE,
     which can be either an octal number, or a symbolic mode as in
     `chmod', with 0 as the point of departure (*note File
     permissions::.).  The default mode is 0755--read, write, and
     execute for the owner, and read and execute for group and other.
`-o OWNER'
`--owner=OWNER'
     If `install' has appropriate privileges (is run as root), set the
     ownership of installed files or directories to OWNER. The default
     is `root'.  OWNER may be either a user name or a numeric user ID.
`--strip'
     Strip the symbol tables from installed binary executables.
File: fileutils.info,  Node: mv invocation,  Next: rm invocation,  Prev: install invocation,  Up: Basic operations
`mv': Move (rename) files
=========================
   `mv' moves or renames files (or directories).  Synopsis:
     mv [OPTION]... SOURCE DEST
     mv [OPTION]... SOURCE... DIRECTORY
   If the last argument names an existing directory, `mv' moves each
other given file into a file with the same name in that directory.
Otherwise, if only two files are given, it renames the first as the
second.  It is an error if the last argument is not a directory and
more than two files are given.
   `mv' can move only regular files across filesystems.
   If a destination file exists but is normally unwritable, standard
input is a terminal, and the `-f' or `--force' option is not given,
`mv' prompts the user for whether to replace the file.  (You might own
the file, or have write permission on its directory.)  If the response
does not begin with `y' or `Y', the file is skipped.
   The program accepts the following options.  Also see *Note Common
options::.
`--backup'
     Make backups of files that are about to be overwritten or removed.
     *Note Backup options::.
`--force'
     Remove existing destination files and never prompt the user.
`--interactive'
     Prompt whether to overwrite each existing destination file,
     regardless of its permissions.  If the response does not begin
     with `y' or `Y', the file is skipped.
`--update'
     Do not move a nondirectory that has an existing destination with
     the same or newer modification time.
`--verbose'
     Print the name of each file before moving it.
`-S SUFFIX'
`--suffix=SUFFIX'
     Append SUFFIX to each backup file made with `-b'.  *Note Backup
     options::.
`-V METHOD'
`--version-control=METHOD'
     Change the type of backups made with `-b'.  The METHOD argument
     can be `numbered' (or `t'), `existing' (or `nil'), or `never' (or
     `simple').  *Note Backup options::.
File: fileutils.info,  Node: rm invocation,  Prev: mv invocation,  Up: Basic operations
`rm': Remove files or directories
=================================
   `rm' removes each given FILE.  By default, it does not remove
directories.  Synopsis:
     rm [OPTION]... [FILE]...
   If a file is unwritable, standard input is a terminal, and the `-f'
or `--force' option is not given, or the `-i' or `--interactive' option
*is* given, `rm' prompts the user for whether to remove the file.  If
the response does not begin with `y' or `Y', the file is skipped.
   The program accepts the following options.  Also see *Note Common
options::.
`--directory'
     Remove directories with `unlink' instead of `rmdir', and don't
     require a directory to be empty before trying to unlink it.  Only
     works if you have appropriate privileges.  Because unlinking a
     directory causes any files in the deleted directory to become
     unreferenced, it is wise to `fsck' the filesystem after doing this.
`--force'
     Ignore nonexistent files and never prompt the user.
`--interactive'
     Prompt whether to remove each file.  If the response does not begin
     with `y' or `Y', the file is skipped.
`--recursive'
     Remove the contents of directories recursively.
`--verbose'
     Print the name of each file before removing it.
   One common question is how to remove files whose names being with a
`-'.  GNU `rm', like every program that uses the `getopt' function to
parse its arguments, lets you use the `--' option to indicate that all
following arguments are non-options.  To remove a file called `-f' in
the current directory, you could type either:
     rm -- -f
     rm ./-f
   The Unix `rm' program's use of a single `-' for this purpose
predates the development of the getopt standard syntax.
File: fileutils.info,  Node: Special file types,  Next: Changing file attributes,  Prev: Basic operations,  Up: Top
Special file types
******************
   This chapter describes commands which create special types of files
(and `rmdir', which removes directories, one special file type).
   Although Unix-like operating systems have markedly fewer special file
types than others, not *everything* can be treated only as the
undifferentiated byte stream of "normal files".  For example, when a
file is created or removed, the system must record this information,
which it does in a "directory"--a special type of file.  Although you
can read directories as normal files, if you're curious, in order for
the system to do its job it must impose a structure, a certain order,
on the bytes of the file.  Thus it is a "special" type of file.
   Besides directories, other special file types include named pipes
(FIFOs), symbolic links, sockets, and so-called "special files".
* Menu:
* ln invocation::               Make links between files.
* mkdir invocation::            Make directories.
* mkfifo invocation::           Make FIFOs (named pipes).
* mknod invocation::            Make block or character special files.
* rmdir invocation::            Remove empty directories.
File: fileutils.info,  Node: ln invocation,  Next: mkdir invocation,  Up: Special file types
`ln': Make links between files
==============================
   `ln' makes links between files.  By default, it makes hard links;
with the `-s' option, it makes symbolic (or "soft") links.  Synopses:
     ln [OPTION]... SOURCE [DEST]
     ln [OPTION]... SOURCE... DIRECTORY
   If the last argument names an existing directory, `ln' links each
SOURCE file into a file with the same name in that directory.  (But see
the description of the `--no-dereference' option below.) If only one
file is given, it links that file into the current directory.
Otherwise, if only two files are given, it links the first onto the
second.  It is an error if the last argument is not a directory and more
than two files are given.  By default, it does not remove existing
files.
   A "hard link" is another name for an existing file; the link and the
original are indistinguishable.  (Technically speaking, they share the
same inode, and the inode contains all the information about a
file--indeed, it is not incorrect to say that the inode *is* the file.)
On all existing implementations, you cannot make a hard links to
directories, and hard links cannot cross filesystem boundaries.  (These
restrictions are not mandated by POSIX, however.)
   "Symbolic links" ("symlinks" for short), on the other hand, are a
special file type (which not all kernels support; in particular, system
V release 3 (and older) systems lack symlinks) in which the link file
actually refers to a different file, by name.  When most operations
(opening, reading, writing, and so on) are passed the symbolic link
file, the kernel automatically "dereferences" the link and operates on
the target of the link.  But some operations (e.g., removing) work on
the link file itself, rather than on its target.  *Note Symbolic Links:
(library)Symbolic Links.
   The program accepts the following options.  Also see *Note Common
options::.
`--backup'
     Make backups of files that are about to be overwritten or removed.
     *Note Backup options::.
`--directory'
     Allow the super-user to make hard links to directories.
`--force'
     Remove existing destination files.
`--interactive'
     Prompt whether to remove existing destination files.
`--no-dereference'
     When used with `--force' and an explicit destination that is a
     symlink to a directory, remove (or move it with `--backup') that
     symlink before making any link.
     When the destination is an actual directory (not a symlink to one),
     there is no ambiguity.  The link is created in that directory.
     But when the specified destination is a symlink to a directory,
     there are two ways to treat the user's request.  `ln' can treat
     the destination just as it would a normal directory and create the
     link in it.  On the other hand, the destination can be viewed as a
     non-directory--as the symlink itself.  In that case, `ln' must
     delete or backup that symlink before creating the new link.  The
     default is to treat a destination that is a symlink to a directory
     just like a directory.
`--symbolic'
     Make symbolic links instead of hard links.  This option merely
     produces an error message on systems that do not support symbolic
     links.
`--verbose'
     Print the name of each file before linking it.
`-S SUFFIX'
`--suffix=SUFFIX'
     Append SUFFIX to each backup file made with `-b'.  *Note Backup
     options::.
`-V METHOD'
`--version-control=METHOD'
     Change the type of backups made with `-b'.  The METHOD argument
     can be `numbered' (or `t'), `existing' (or `nil'), or `never' (or
     `simple').  *Note Backup options::.
File: fileutils.info,  Node: mkdir invocation,  Next: mkfifo invocation,  Prev: ln invocation,  Up: Special file types
`mkdir': Make directories
=========================
   `mkdir' creates directories with the specified names.  Synopsis:
     mkdir [OPTION]... NAME...
   It is not an error if a NAME is already a directory; `mkdir' simply
proceeds.  But if a NAME is an existing file and is anything but a
directory, `mkdir' complains.
   The program accepts the following options.  Also see *Note Common
options::.
`-m MODE'
`--mode=MODE'
     Set the mode of created directories to MODE, which is symbolic as
     in `chmod' and uses 0777 (read, write and execute allowed for
     everyone) minus the bits set in the umask for the point of the
     departure.  *Note File permissions::.
`--parents'
     Make any missing parent directories for each argument.  The mode
     for parent directories is set to the umask modified by `u+wx'.
     Ignore arguments corresponding to existing directories.
File: fileutils.info,  Node: mkfifo invocation,  Next: mknod invocation,  Prev: mkdir invocation,  Up: Special file types
`mkfifo': Make FIFOs (named pipes)
==================================
   `mkfifo' creates FIFOs (also called "named pipes") with the
specified names.  Synopsis:
     mkfifo [OPTION] NAME...
   A "FIFO" is a special file type that permits independent processes
to communicate.  One process opens the FIFO file for writing, and
another for reading, after which data can flow as with the usual
anonymous pipe in shells or elsewhere.
   The program accepts the following option.  Also see *Note Common
options::.
`-m MODE'
`--mode=MODE'
     Set the mode of created FIFOs to MODE, which is symbolic as in
     `chmod' and uses 0666 (read and write allowed for everyone) minus
     the bits set in the umask for the point of departure.  *Note File
     permissions::.
File: fileutils.info,  Node: mknod invocation,  Next: rmdir invocation,  Prev: mkfifo invocation,  Up: Special file types
`mknod': Make block or character special files
==============================================
   `mknod' creates a FIFO, character special file, or block special
file with the specified name.  Synopsis:
     mknod [OPTION]... NAME TYPE [MAJOR MINOR]
   Unlike the phrase "special file type" above, the term "special file"
has a technical meaning on Unix: something that can generate or receive
data.  Usually this corresponds to a physical piece of hardware, e.g.,
a printer or a disk.  (These files are typically created at
system-configuration time.)  The `mknod' command is what creates files
of this type.  Such devices can be read either a character at a time or
a "block" (many characters) at a time, hence we say there are "block
special" files and "character special" files.
   The arguments after NAME specify the type of file to make:
     for a FIFO
     for a block (buffered) special file
     for a character (buffered) special file
     for a character (unbuffered) special file
   When making a block or character special file, the major and minor
device numbers must be given after the file type.
   The program accepts the following option.  Also see *Note Common
options::.
`-m MODE'
`--mode=MODE'
     Set the mode of created files to MODE, which is symbolic as in
     `chmod' and uses 0666 minus the bits set in the umask as the point
     of departure.  *Note File permissions::.
File: fileutils.info,  Node: rmdir invocation,  Prev: mknod invocation,  Up: Special file types
`rmdir': Remove empty directories
=================================
   `rmdir' removes empty directories.  Synopsis:
     rmdir [OPTION]... DIRECTORY...
   If any DIRECTORY argument does not refer to an existing empty
directory, it is an error.
   The program accepts the following option.  Also see *Note Common
options::.
`--parents'
     Remove any parent directories that become empty after an argument
     DIRECTORY is removed.
   *Note rm invocation::, for how to remove non-empty directories
(recursively).
File: fileutils.info,  Node: Changing file attributes,  Next: Disk usage,  Prev: Special file types,  Up: Top
Changing file attributes
************************
   Files are not merely contents, a name, and a file type (*note
Special file types::.).  They also have an owner (a userid), a group (a
group id), permissions (what the owner can do with the file, what
people in the group can do, and what everyone else can do), various
timestamps, and other information.  Collectively, we call all this a
file's "attributes".
   These commands change file attributes.
* Menu:
* chown invocation::            Change file owners and groups.
* chgrp invocation::            Change file groups.
* chmod invocation::            Change access permissions.
* touch invocation::            Change file timestamps.
File: fileutils.info,  Node: chown invocation,  Next: chgrp invocation,  Up: Changing file attributes
`chown': Change file owner and group
====================================
   `chown' changes the user and/or group ownership of each given file.
Synopsis:
     chown [OPTION]... NEW-OWNER FILE...
   The first non-option argument, NEW-OWNER, specifies the new owner
and/or group, as follows (with no embedded white space):
     [OWNER] [ [:.] [GROUP] ]
   Specifically:
OWNER
     If only an OWNER (a user name or numeric user id) is given, that
     user is made the owner of each given file, and the files' group is
     not changed.
OWNER`.'GROUP
OWNER`:'GROUP
     If the OWNER is followed by a colon or dot and a GROUP (a group
     name or numeric group id), with no spaces between them, the group
     ownership of the files is changed as well (to GROUP).
OWNER`.'
OWNER`:'
     If a colon or dot but no group name follows OWNER, that user is
     made the owner of the files and the group of the files is changed
     to OWNER's login group.
`.'GROUP
`:'GROUP
     If the colon or dot and following GROUP are given, but the owner
     is omitted, only the group of the files is changed; in this case,
     `chown' performs the same function as `chgrp'.
   The program accepts the following options.  Also see *Note Common
options::.
`--changes'
     Verbosely describe the action for each FILE whose ownership
     actually changes.
`--silent'
`--quiet'
     Do not print error messages about files whose ownership cannot be
     changed.
`--verbose'
     Verbosely describe the action (or non-action) taken for every FILE.
`--recursive'
     Recursively change ownership of directories and their contents.
File: fileutils.info,  Node: chgrp invocation,  Next: chmod invocation,  Prev: chown invocation,  Up: Changing file attributes
`chgrp': Change group ownership
===============================
   `chgrp' changes the group ownership of each given FILE to GROUP,
which can be either a group name or a numeric group id.  Synopsis:
     chgrp [OPTION]... GROUP FILE...
   The program accepts the following options.  Also see *Note Common
options::.
`--changes'
     Verbosely describe the action for each FILE whose group actually
     changes.
`--silent'
`--quiet'
     Do not print error messages about files whose group cannot be
     changed.
`--verbose'
     Verbosely describe the action or non-action taken for every FILE.
`--recursive'
     Recursively change the group ownership of directories and their
     contents.
File: fileutils.info,  Node: chmod invocation,  Next: touch invocation,  Prev: chgrp invocation,  Up: Changing file attributes
`chmod': Change access permissions
==================================
   `chmod' changes the access permissions of the named files.  Synopsis:
     chmod [OPTION]... MODE FILE...
   `chmod' never changes the permissions of symbolic links, since the
`chmod' system call cannot change their permissions.  This is not a
problem since the permissions of symbolic links are never used.
However, for each symbolic link listed on the command line, `chmod'
changes the permissions of the pointed-to file.  In contrast, `chmod'
ignores symbolic links encountered during recursive directory
traversals.
   The first non-option argument, MODE, specifies the new permissions.
See the section below for details.
   The program accepts the following options.  Also see *Note Common
options::.
`--changes'
     Verbosely describe the action for each FILE whose permissions
     actually changes.
`--silent'
`--quiet'
     Do not print error messages about files whose permissions cannot be
     changed.
`--verbose'
     Verbosely describe the action or non-action taken for every FILE.
`--recursive'
     Recursively change permissions of directories and their contents.
File: fileutils.info,  Node: touch invocation,  Prev: chmod invocation,  Up: Changing file attributes
`touch': Change file timestamps
===============================
   `touch' changes the access and/or modification times of the
specified files.  Synopsis:
     touch [OPTION]... FILE...
   If the first FILE would be a valid argument to the `-t' option and
no timestamp is given with any of the `-d', `-r', or `-t' options and
the `--' argument is not given, that argument is interpreted as the
time for the other files instead of as a filename.
   Any FILE that does not exist is created empty.
   If changing both the access and modification times to the current
time, `touch' can change the timestamps for files that the user running
it does not own but has write permission for.  Otherwise, the user must
own the files.
   The program accepts the following options.  Also see *Note Common
options::.
`--time=atime'
`--time=access'
`--time=use'
     Change the access time only.
`--no-create'
     Do not create files that do not exist.
`--date=time'
     Use TIME instead of the current time.  It can contain month names,
     timezones, `am' and `pm', etc.  *Note `date' invocation:
     (sh-utils)date invocation.
     Ignored; for compatibility with BSD versions of `touch'.
`--time=mtime'
`--time=modify'
     Change the modification time only.
`-r REFERENCE-FILE'
`--file=REFERENCE-FILE'
     Use the times of REFERENCE-FILE instead of the current time.
`-t MMDDhhmm[[CC]YY][.ss]'
     Use the argument (months, days, hours, minutes, optional century
     and years, optional seconds) instead of the current time.
File: fileutils.info,  Node: Disk usage,  Next: Index,  Prev: Changing file attributes,  Up: Top
Disk usage
**********
   No disk can hold an infinite amount of data.  These commands report
on how much disk storage is in use or available.  (This has nothing
much to do with how much *main memory*, i.e., RAM, a program is using
when it runs; for that, you want `ps' or `pstat' or `swap' or some such
command.)
* Menu:
* df invocation::               Report filesystem disk space usage.
* du invocation::               Estimate file space usage.
* sync invocation::        Synchronize memory and disk.
File: fileutils.info,  Node: df invocation,  Next: du invocation,  Up: Disk usage
`df': Report filesystem disk space usage
========================================
   `df' reports the amount of disk space used and available on
filesystems.  Synopsis:
     df [OPTION]... [FILE]...
   With no arguments, `df' reports the space used and available on all
currently mounted filesystems (of all types).  Otherwise, `df' reports
on the filesystem containing each argument FILE.
   Disk space is shown in 1024-byte blocks by default, unless the
environment variable `POSIXLY_CORRECT' is set, in which case 512-byte
blocks are used (unless the `-k' option is given).
   If an argument FILE is a disk device file containing a mounted
filesystem, `df' shows the space available on that filesystem rather
than on the filesystem containing the device node (i.e., the root
filesystem).  GNU `df' does not attempt to determine the disk usage on
unmounted filesystems, because on most kinds of systems doing so
requires extremely nonportable intimate knowledge of filesystem
structures.
   The program accepts the following options.  Also see *Note Common
options::.
`--all'
     Include in the listing filesystems that have 0 blocks, which are
     omitted by default.  Such filesystems are typically special-purpose
     pseudo-filesystems, such as automounter entries.  Filesystems of
     type "ignore" or "auto", supported by some operating systems, are
     only included in the listing if this option is specified.
`--inodes'
     List inode usage information instead of block usage.  An inode
     (short for index node) is contains information about a file such
     as its owner, permissions, timestamps, and location on the disk.
`--kilobytes'
     Print sizes in 1024-byte blocks.  This overrides the environment
     variable `POSIXLY_CORRECT'.
`--no-sync'
     Do not invoke the `sync' system call before getting any usage data.
     This may make `df' run significantly faster on systems with many
     disks, but on some systems the results may be slightly out of date.
`--portability'
     Use the POSIX output format.  This is like the default format
     except that the information about each filesystem is always
     printed on exactly one line; a mount device is never put on a line
     by itself.  This means that if the mount device name is more than
     20 characters long (e.g., for some network mounts), the columns
     are misaligned.
`--sync'
     Invoke the `sync' system call before getting any usage data.  On
     some systems, doing this yields more up to date results, but in
     general this option makes `df' much slower, especially when there
     are many or very busy filesystems.
`-t FSTYPE'
`--type=FSTYPE'
     Limit the listing to filesystems of type FSTYPE.  Multiple
     filesystem types can be specified by giving multiple `-t' options.
     By default, nothing is omitted.
`--print-type'
     Print each filesystem's type.  The types printed here are the same
     ones you can include or exclude with `-t' and `-x'.  The particular
     types printed are whatever is supported by the system.  Here are
     some of the common names (this list is certainly not exhaustive):
    `nfs'
          An NFS filesystem, i.e., one mounted over a network from
          another machine.  This is the one type name which seems to be
          used uniformly by all systems.
    `4.2, ufs, efs...'
          A filesystem on a locally-mounted hard disk.  (The system
          might even support more than one type here; Linux does.)
    `hsfs, cdfs'
          A filesystem on a CD-ROM drive.  HP-UX uses `cdfs', most other
          systems use `hsfs' (`hs' for `High Sierra').
    `pcfs'
          An MS-DOS filesystem, usually on a diskette.
`-x FSTYPE'
`--exclude-type=FSTYPE'
     Limit the listing to filesystems not of type FSTYPE.  Multiple
     filesystem types can be eliminated by giving multiple `-x'
     options.  By default, no filesystem types are omitted.
     Ignored; for compatibility with System V versions of `df'.
File: fileutils.info,  Node: du invocation,  Next: sync invocation,  Prev: df invocation,  Up: Disk usage
`du': Estimate file space usage
===============================
   `du' reports the amount of disk space used by the specified files
and for each subdirectory (of directory arguments).  Synopsis:
     du [OPTION]... [FILE]...
   With no arguments, `du' reports the disk space for the current
directory.  The output is in 1024-byte units by default, unless the
environment variable `POSIXLY_CORRECT' is set, in which case 512-byte
blocks are used (unless `-k' is specified).
   The program accepts the following options.  Also see *Note Common
options::.
`--all'
     Show counts for all files, not just directories.
`--bytes'
     Print sizes in bytes, instead of kilobytes.
`--total'
     Print a grand total of all arguments after all arguments have been
     processed.  This can be used to find out the total disk usage of a
     given set of files or directories.
`--dereference-args'
     Dereference symbolic links that are command line arguments.  Does
     not affect other symbolic links.  This is helpful for finding out
     the disk usage of directories, such as `/usr/tmp', which are often
     symbolic links.
`--kilobytes'
     Print sizes in kilobytes.  This overrides the environment variable
     `POSIXLY_CORRECT'.
`--count-links'
     Count the size of all files, even if they have appeared already
     (as a hard link).
`--dereference'
     Dereference symbolic links (show the disk space used by the file
     or directory that the link points to instead of the space used by
     the link).
`--summarize'
     Display only a total for each argument.
`--separate-dirs'
     Report the size of each directory separately, not including the
     sizes of subdirectories.
`--one-file-system'
     Skip directories that are on different filesystems from the one
     that the argument being processed is on.
   On BSD systems, `du' reports sizes that are half the correct values
for files that are NFS-mounted from HP-UX systems.  On HP-UX systems,
it reports sizes that are twice the correct values for files that are
NFS-mounted from BSD systems.  This is due to a flaw in HP-UX; it also
affects the HP-UX `du' program.
File: fileutils.info,  Node: sync invocation,  Prev: du invocation,  Up: Disk usage
`sync': Synchronize data on disk with memory
============================================
   `sync' writes any data buffered in memory out to disk.  This can
include (but is not limited to) modified superblocks, modified inodes,
and delayed reads and writes.  This must be implemented by the kernel;
The `sync' program does nothing but exercise the `sync' system call.
   The kernel keeps data in memory to avoid doing (relatively slow) disk
reads and writes.  This improves performance, but if the computer
crashes, data may be lost or the filesystem corrupted as a result.
`sync' ensures everything in memory is written to disk.
   Any arguments are ignored, except for a lone `--help' or `--version'
(*note Common options::.).
File: fileutils.info,  Node: Index,  Prev: Disk usage,  Up: Top
Index
*****
* Menu:
* - and Unix rm:                        rm invocation.
* -all:                                 df invocation.
* -all:                                 du invocation.
* -all:                                 Which files are listed.
* -almost-all:                          Which files are listed.
* -archive:                             cp invocation.
* -backup:                              mv invocation.
* -backup:                              Backup options.
* -backup:                              cp invocation.
* -backup:                              ln invocation.
* -bytes:                               du invocation.
* -changes:                             chgrp invocation.
* -changes:                             chown invocation.
* -changes:                             chmod invocation.
* -classify:                            General output formatting.
* -count-links:                         du invocation.
* -date:                                touch invocation.
* -dereference:                         du invocation.
* -dereference:                         Which files are listed.
* -dereference-args:                    du invocation.
* -directory:                           ln invocation.
* -directory:                           install invocation.
* -directory:                           rm invocation.
* -directory:                           Which files are listed.
* -dired:                               What information is listed.
* -escape:                              Formatting the filenames.
* -exclude-type:                        df invocation.
* -file:                                touch invocation.
* -force:                               rm invocation.
* -force:                               ln invocation.
* -force:                               mv invocation.
* -force:                               cp invocation.
* -format:                              What information is listed.
* -format:                              General output formatting.
* -format:                              General output formatting.
* -format:                              General output formatting.
* -format:                              General output formatting.
* -full-time:                           General output formatting.
* -group:                               install invocation.
* -help:                                Common options.
* -hide-control-chars:                  Formatting the filenames.
* -ignore-backups:                      Which files are listed.
* -ignore=PATTERN:                      Which files are listed.
* -inode:                               What information is listed.
* -inodes:                              df invocation.
* -interactive:                         ln invocation.
* -interactive:                         rm invocation.
* -interactive:                         mv invocation.
* -interactive:                         cp invocation.
* -kilobytes:                           du invocation.
* -kilobytes:                           General output formatting.
* -kilobytes:                           df invocation.
* -link:                                cp invocation.
* -literal:                             Formatting the filenames.
* -mode:                                install invocation.
* -mode:                                mknod invocation.
* -mode:                                mkfifo invocation.
* -mode:                                mkdir invocation.
* -no-create:                           touch invocation.
* -no-dereference:                      ln invocation.
* -no-dereference:                      cp invocation.
* -no-group:                            What information is listed.
* -no-sync:                             df invocation.
* -numeric-uid-gid:                     General output formatting.
* -one-file-system:                     cp invocation.
* -one-file-system:                     du invocation.
* -owner:                               install invocation.
* -parents:                             mkdir invocation.
* -parents:                             cp invocation.
* -parents:                             rmdir invocation.
* -portability:                         df invocation.
* -preserve:                            cp invocation.
* -print-type:                          df invocation.
* -quiet:                               chmod invocation.
* -quiet:                               chgrp invocation.
* -quiet:                               chown invocation.
* -quote-name:                          Formatting the filenames.
* -recursive:                           Which files are listed.
* -recursive:                           chmod invocation.
* -recursive:                           rm invocation.
* -recursive:                           chown invocation.
* -recursive:                           cp invocation.
* -recursive:                           chgrp invocation.
* -reverse:                             Sorting the output.
* -separate-dirs:                       du invocation.
* -silent:                              chgrp invocation.
* -silent:                              chmod invocation.
* -silent:                              chown invocation.
* -size:                                What information is listed.
* -sort:                                Sorting the output.
* -sort:                                Sorting the output.
* -sort:                                Sorting the output.
* -sort:                                Sorting the output.
* -strip:                               install invocation.
* -suffix:                              cp invocation.
* -suffix:                              ln invocation.
* -suffix:                              Backup options.
* -suffix:                              mv invocation.
* -summarize:                           du invocation.
* -symbolic:                            ln invocation.
* -symbolic-link:                       cp invocation.
* -sync:                                df invocation.
* -tabsize:                             General output formatting.
* -time:                                touch invocation.
* -time:                                Sorting the output.
* -time:                                Sorting the output.
* -time:                                touch invocation.
* -total:                               du invocation.
* -type:                                df invocation.
* -update:                              cp invocation.
* -update:                              mv invocation.
* -verbose:                             ln invocation.
* -verbose:                             chmod invocation.
* -verbose:                             mv invocation.
* -verbose:                             cp invocation.
* -verbose:                             rm invocation.
* -verbose:                             chown invocation.
* -verbose:                             chgrp invocation.
* -version:                             Common options.
* -version-control:                     cp invocation.
* -version-control:                     ln invocation.
* -version-control:                     mv invocation.
* -version-control:                     Backup options.
* -width:                               General output formatting.
* -1:                                   General output formatting.
* -A:                                   Which files are listed.
* -a:                                   touch invocation.
* -a:                                   du invocation.
* -a:                                   Which files are listed.
* -a:                                   df invocation.
* -a:                                   cp invocation.
* -b:                                   cp invocation.
* -b:                                   Formatting the filenames.
* -B:                                   Which files are listed.
* -b:                                   Backup options.
* -b:                                   mv invocation.
* -b:                                   ln invocation.
* -b:                                   du invocation.
* -c:                                   du invocation.
* -C:                                   General output formatting.
* -c:                                   chgrp invocation.
* -c:                                   Sorting the output.
* -c:                                   install invocation.
* -c:                                   touch invocation.
* -c:                                   chown invocation.
* -c:                                   chmod invocation.
* -d:                                   rm invocation.
* -d:                                   Which files are listed.
* -d:                                   ln invocation.
* -d:                                   touch invocation.
* -D:                                   What information is listed.
* -d:                                   cp invocation.
* -d:                                   install invocation.
* -D:                                   du invocation.
* -f:                                   Sorting the output.
* -f:                                   chown invocation.
* -f:                                   cp invocation.
* -f:                                   chgrp invocation.
* -f:                                   mv invocation.
* -f:                                   rm invocation.
* -F:                                   General output formatting.
* -f:                                   chmod invocation.
* -f:                                   ln invocation.
* -F:                                   ln invocation.
* -g:                                   ls invocation.
* -g:                                   install invocation.
* -G:                                   What information is listed.
* -i:                                   What information is listed.
* -i:                                   ln invocation.
* -I:                                   Which files are listed.
* -i:                                   df invocation.
* -i:                                   cp invocation.
* -i:                                   rm invocation.
* -i:                                   mv invocation.
* -k:                                   df invocation.
* -k:                                   General output formatting.
* -k:                                   du invocation.
* -L:                                   du invocation.
* -l:                                   du invocation.
* -l:                                   cp invocation.
* -l:                                   What information is listed.
* -L:                                   Which files are listed.
* -m:                                   mknod invocation.
* -m:                                   install invocation.
* -m:                                   General output formatting.
* -m:                                   mkdir invocation.
* -m:                                   mkfifo invocation.
* -m:                                   touch invocation.
* -n:                                   General output formatting.
* -n:                                   ln invocation.
* -N:                                   Formatting the filenames.
* -o:                                   install invocation.
* -p:                                   rmdir invocation.
* -p:                                   mkdir invocation.
* -P:                                   cp invocation.
* -P:                                   df invocation.
* -p:                                   cp invocation.
* -q:                                   Formatting the filenames.
* -Q:                                   Formatting the filenames.
* -R:                                   chown invocation.
* -R:                                   chgrp invocation.
* -r:                                   touch invocation.
* -r:                                   Sorting the output.
* -r:                                   rm invocation.
* -R:                                   Which files are listed.
* -R:                                   rm invocation.
* -R:                                   chmod invocation.
* -R:                                   cp invocation.
* -s:                                   cp invocation.
* -S:                                   Sorting the output.
* -S:                                   mv invocation.
* -S:                                   du invocation.
* -S:                                   Backup options.
* -S:                                   ln invocation.
* -s:                                   What information is listed.
* -s:                                   ln invocation.
* -s:                                   install invocation.
* -S:                                   cp invocation.
* -s:                                   du invocation.
* -T:                                   General output formatting.
* -t:                                   Sorting the output.
* -t:                                   df invocation.
* -T:                                   df invocation.
* -u:                                   cp invocation.
* -u:                                   mv invocation.
* -u:                                   Sorting the output.
* -U:                                   Sorting the output.
* -v:                                   ln invocation.
* -v:                                   rm invocation.
* -v:                                   mv invocation.
* -v:                                   chmod invocation.
* -V:                                   cp invocation.
* -V:                                   ln invocation.
* -v:                                   cp invocation.
* -v:                                   chgrp invocation.
* -V:                                   mv invocation.
* -V:                                   Backup options.
* -v:                                   chown invocation.
* -w:                                   General output formatting.
* -x:                                   du invocation.
* -x:                                   cp invocation.
* -x:                                   General output formatting.
* -x:                                   df invocation.
* -X:                                   Sorting the output.
* 4.2 filesystem type:                  df invocation.
* -, removing files beginning with:     rm invocation.
* access time, changing:                touch invocation.
* access permissions, changing:         chmod invocation.
* access time, sorting files by:        Sorting the output.
* across, listing files:                General output formatting.
* adding permissions:                   Setting Permissions.
* alternate ebcdic, converting to:      dd invocation.
* append-only directories:              Mode Structure.
* appropriate privileges:               install invocation.
* ascii, converting to:                 dd invocation.
* atime, changing:                      touch invocation.
* atime, sorting files by:              Sorting the output.
* attributes, file:                     Changing file attributes.
* automounter filesystems:              df invocation.
* b for block special file:             mknod invocation.
* backslash sequences for filenames:    Formatting the filenames.
* backup files, ignoring:               Which files are listed.
* backup files, type made:              Backup options.
* backup options:                       Backup options.
* backup suffix:                        Backup options.
* backups, making:                      cp invocation.
* backups, making:                      mv invocation.
* backups, making:                      Backup options.
* backups, making:                      ln invocation.
* block (space-padding):                dd invocation.
* block size:                           dd invocation.
* block size of conversion:             dd invocation.
* block size of input:                  dd invocation.
* block size of output:                 dd invocation.
* block special files:                  mknod invocation.
* block special files, creating:        mknod invocation.
* bs:                                   dd invocation.
* buffered character file:              mknod invocation.
* bugs, reporting:                      Introduction.
* byte-swapping:                        dd invocation.
* c for character special file:         mknod invocation.
* cbs:                                  dd invocation.
* CD-ROM filesystem type:               df invocation.
* cdfs filesystem type:                 df invocation.
* changed files, verbosely describing:  chgrp invocation.
* changed owners, verbosely describing: chown invocation.
* changing access permissions:          chmod invocation.
* changing file attributes:             Changing file attributes.
* changing file ownership:              chown invocation.
* changing file timestamps:             touch invocation.
* changing group ownership:             chown invocation.
* changing group ownership:             chgrp invocation.
* changing special permissions:         Changing Special Permissions.
* character special files:              mknod invocation.
* character special files, creating:    mknod invocation.
* chgrp:                                chgrp invocation.
* chmod:                                chmod invocation.
* chown:                                chown invocation.
* COLUMNS:                              General output formatting.
* commas, outputting between files:     General output formatting.
* common options:                       Common options.
* conditional executability:            Conditional Executability.
* conv:                                 dd invocation.
* converstion block size:               dd invocation.
* converting while copying a file:      dd invocation.
* copying directories recursively:      cp invocation.
* copying existing permissions:         Copying Permissions.
* copying files and directories:        cp invocation.
* copying files and setting attributes: install invocation.
* count:                                dd invocation.
* cp:                                   cp invocation.
* crashes and corruption:               sync invocation.
* creating directories:                 mkdir invocation.
* creating FIFOs (named pipes):         mkfifo invocation.
* creating links (hard or soft):        ln invocation.
* ctime, sorting by:                    Sorting the output.
* dd:                                   dd invocation.
* dereferencing symbolic links:         ln invocation.
* device file, disk:                    df invocation.
* df:                                   df invocation.
* dir:                                  dir invocation.
* directories, copying:                 cp invocation.
* directories, copying recursively:     cp invocation.
* directories, creating:                mkdir invocation.
* directories, creating with given attributes: install invocation.
* directories, removing (recursively):  rm invocation.
* directories, removing empty:          rmdir invocation.
* directories, removing with unlink:    rm invocation.
* directory listing:                    ls invocation.
* directory listing, brief:             dir invocation.
* directory listing, recursive:         Which files are listed.
* directory listing, verbose:           vdir invocation.
* dired Emacs mode support:             What information is listed.
* disk device file:                     df invocation.
* disk usage:                           Disk usage.
* disk usage by filesystem:             df invocation.
* disk usage for files:                 du invocation.
* diskette filesystem:                  df invocation.
* DOS filesystem:                       df invocation.
* du:                                   du invocation.
* ebcdic, converting to:                dd invocation.
* efs filesystem type:                  df invocation.
* empty files, creating:                touch invocation.
* error messages, omitting:             chmod invocation.
* error messages, omitting:             chgrp invocation.
* error messages, omitting:             chown invocation.
* executables and file type, marking:   General output formatting.
* execute permission:                   Mode Structure.
* execute permission, symbolic:         Setting Permissions.
* existing backup method:               Backup options.
* extension, sorting files by:          Sorting the output.
* FIFOs, creating:                      mkfifo invocation.
* file attributes, changing:            Changing file attributes.
* file information, preserving:         cp invocation.
* file ownership, changing:             chown invocation.
* file permissions:                     File permissions.
* file permissions, numeric:            Numeric Modes.
* file space usage:                     du invocation.
* file timestamps, changing:            touch invocation.
* file type and executables, marking:   General output formatting.
* file type, marking:                   General output formatting.
* file types:                           Special file types.
* file types, special:                  Special file types.
* file utilities:                       Top.
* files beginning with -, removing:     rm invocation.
* files, copying:                       cp invocation.
* filesystem disk usage:                df invocation.
* filesystem space, retrieving current data more slowly: df invocation.
* filesystem space, retrieving old data more quickly: df invocation.
* filesystem types, limiting output to certain: df invocation.
* filesystem types, printing:           df invocation.
* filesystems and hard links:           ln invocation.
* filesystems, omitting copying to different: cp invocation.
* fsck:                                 rm invocation.
* giving away permissions:              Umask and Protection.
* grand total of disk space:            du invocation.
* group owner, default:                 Mode Structure.
* group ownership of installed files, setting: install invocation.
* group ownership, changing:            chgrp invocation.
* group ownerships, changing:           chown invocation.
* group, permissions for:               Setting Permissions.
* hard links to directories:            ln invocation.
* hard links, creating:                 ln invocation.
* hard links, preserving:               cp invocation.
* help, online:                         Common options.
* High Sierra filesystem:               df invocation.
* history:                              Introduction.
* holes, copying:                       cp invocation.
* horizontal, listing files:            General output formatting.
* hsfs filesystem type:                 df invocation.
* ibs:                                  dd invocation.
* if:                                   dd invocation.
* ignore filesystems:                   df invocation.
* inode number, printing:               What information is listed.
* inode usage:                          df invocation.
* inodes, written buffered:             sync invocation.
* input block size:                     dd invocation.
* install:                              install invocation.
* introduction:                         Introduction.
* lcase, converting to:                 dd invocation.
* leading directories, creating missing: install invocation.
* links, creating:                      ln invocation.
* Linux filesystem types:               df invocation.
* ln:                                   ln invocation.
* local filesystem types:               df invocation.
* long ls format:                       What information is listed.
* ls:                                   ls invocation.
* Makefiles, installing programs in:    install invocation.
* manipulating files:                   Basic operations.
* mkdir:                                mkdir invocation.
* mkfifo:                               mkfifo invocation.
* mknod:                                mknod invocation.
* modes and umask:                      Umask and Protection.
* modes of created directories, setting: mkdir invocation.
* modes of created FIFOs, setting:      mkfifo invocation.
* modification time, sorting files by:  Sorting the output.
* modify time, changing:                touch invocation.
* MS-DOS filesystem:                    df invocation.
* mtime, changing:                      touch invocation.
* multiple changes to permissions:      Multiple Changes.
* multipliers after numbers:            dd invocation.
* mv:                                   mv invocation.
* named pipes, creating:                mkfifo invocation.
* newer files, copying only:            cp invocation.
* newer files, moving only:             mv invocation.
* NFS filesystem type:                  df invocation.
* NFS mounts from BSD to HP-UX:         What information is listed.
* NFS mounts from BSD to HP-UX:         du invocation.
* noerror:                              dd invocation.
* non-directories, copying as special files: cp invocation.
* none, sorting option for ls:          Sorting the output.
* notrunc:                              dd invocation.
* numbered backup method:               Backup options.
* numeric modes:                        Numeric Modes.
* numeric uid and gid:                  General output formatting.
* obs:                                  dd invocation.
* octal numbers for file modes:         Numeric Modes.
* of:                                   dd invocation.
* one filesystem, restricting du to:    du invocation.
* one-line output format:               df invocation.
* other permissions:                    Setting Permissions.
* output block size:                    dd invocation.
* output format, portable:              df invocation.
* owner of file, permissions for:       Setting Permissions.
* owner, default:                       Mode Structure.
* ownership of installed files, setting: install invocation.
* p for FIFO file:                      mknod invocation.
* parent directories and cp:            cp invocation.
* parent directories, creating:         mkdir invocation.
* parent directories, creating missing: install invocation.
* parent directories, removing:         rmdir invocation.
* PC filesystem:                        df invocation.
* pcfs:                                 df invocation.
* permissions of files:                 File permissions.
* permissions of installed files, setting: install invocation.
* permissions, changing access:         chmod invocation.
* permissions, copying existing:        Copying Permissions.
* permissions, for changing file timestamps: touch invocation.
* portable output format:               df invocation.
* POSIX output format:                  df invocation.
* POSIX.2:                              Introduction.
* POSIXLY_CORRECT:                      df invocation.
* POSIXLY_CORRECT, overridden by df -k: df invocation.
* POSIXLY_CORRECT, overridden by du -k: du invocation.
* POSIXLY_CORRECT, overridden by ls -k: General output formatting.
* POSIXLY_CORRECT, overrides ls -s:     What information is listed.
* prompting, and ln:                    ln invocation.
* prompting, and mv:                    mv invocation.
* prompting, and rm:                    rm invocation.
* prompts, forcing:                     mv invocation.
* prompts, omitting:                    mv invocation.
* read system call, and holes:          cp invocation.
* read errors, ignoring:                dd invocation.
* read permission:                      Mode Structure.
* read permission, symbolic:            Setting Permissions.
* recursive directory listing:          Which files are listed.
* recursively changing access permissions: chmod invocation.
* recursively changing file ownership:  chown invocation.
* recursively changing group ownership: chgrp invocation.
* recursively copying directories:      cp invocation.
* removing empty directories:           rmdir invocation.
* removing files or directories:        rm invocation.
* removing permissions:                 Setting Permissions.
* reverse sorting:                      Sorting the output.
* rm:                                   rm invocation.
* rmdir:                                rmdir invocation.
* root as default owner:                install invocation.
* seek:                                 dd invocation.
* setgid:                               Mode Structure.
* setting permissions:                  Setting Permissions.
* setuid:                               Mode Structure.
* simple backup method:                 Backup options.
* SIMPLE_BACKUP_SUFFIX:                 Backup options.
* single-column output of files:        General output formatting.
* size of files, reporting:             What information is listed.
* size of files, sorting files by:      Sorting the output.
* skip:                                 dd invocation.
* sorting ls output:                    Sorting the output.
* special file types:                   Special file types.
* special file types:                   Special file types.
* special files:                        mknod invocation.
* status time, sorting by:              Sorting the output.
* sticky:                               Mode Structure.
* stripping symbol table information:   install invocation.
* subtracting permissions:              Setting Permissions.
* superblock, writing:                  sync invocation.
* swab (byte-swapping):                 dd invocation.
* swap space, saving text image in:     Mode Structure.
* symbol table information, stripping:  install invocation.
* symbolic (soft) links, creating:      ln invocation.
* symbolic links, copying:              cp invocation.
* symbolic links, copying with:         cp invocation.
* symbolic links, dereferencing:        Which files are listed.
* symbolic links, permissions of:       chmod invocation.
* symbolic modes:                       Symbolic Modes.
* sync:                                 sync invocation.
* sync (padding with nulls):            dd invocation.
* synchronize disk and memory:          sync invocation.
* text image, saving in swap space:     Mode Structure.
* time:                                 touch invocation.
* timestamps, changing file:            touch invocation.
* touch:                                touch invocation.
* truncating output file, avoiding:     dd invocation.
* u for unbuffered character special file: mknod invocation.
* ucase, converting to:                 dd invocation.
* ufs filesystem type:                  df invocation.
* umask and modes:                      Umask and Protection.
* unblock:                              dd invocation.
* unbuffered character special file:    mknod invocation.
* unlink:                               rm invocation.
* use time, changing:                   touch invocation.
* use time, sorting files by:           Sorting the output.
* utilities for file handling:          Top.
* vdir:                                 vdir invocation.
* verbose ls format:                    What information is listed.
* version number, finding:              Common options.
* version-control Emacs variable:       Backup options.
* VERSION_CONTROL:                      Backup options.
* vertical sorted files in columns:     General output formatting.
* write permission:                     Mode Structure.
* write permission, symbolic:           Setting Permissions.
Tag Table:
Node: Top
Node: Introduction
Node: Common options
Node: Backup options
Node: File permissions
Node: Mode Structure
Node: Symbolic Modes
Node: Setting Permissions
Node: Copying Permissions
12440
Node: Changing Special Permissions
13246
Node: Conditional Executability
15087
Node: Multiple Changes
15709
Node: Umask and Protection
17362
Node: Numeric Modes
18456
Node: Directory listing
20291
Node: ls invocation
20710
Node: Which files are listed
22154
Node: What information is listed
23345
Node: Sorting the output
26198
Node: General output formatting
27962
Node: Formatting the filenames
30499
Node: dir invocation
31143
Node: vdir invocation
31517
Node: Basic operations
31819
Node: cp invocation
32376
Node: dd invocation
36278
Node: install invocation
38760
Node: mv invocation
41092
Node: rm invocation
43105
Node: Special file types
44958
Node: ln invocation
46242
Node: mkdir invocation
50016
Node: mkfifo invocation
51033
Node: mknod invocation
51927
Node: rmdir invocation
53483
Node: Changing file attributes
54109
Node: chown invocation
54918
Node: chgrp invocation
56672
Node: chmod invocation
57525
Node: touch invocation
58842
Node: Disk usage
60508
Node: df invocation
61110
Node: du invocation
65228
Node: sync invocation
67544
Node: Index
68365
End Tag Table