CP/M/CPM_CDROM.iso/simtel/sigm/vols000/vol044/sd-41.doc

Text File | 1984-04-29 | 12KB | 265 lines

                    The SD Directory Program



     This documentation file concerns SD-NEW.ASM and SD-NEW.OBJ,
version  4.1  as  of  October  20,  1981.    Version  4.1  is  a
significant  upgrade  of  the standard "super-directory" program
that most RCP/M systems are  now  using as their "DIR" executor.
SD-41 implements many new features  over version 3, and has been
tested  on  a  wide variety of CP/M systems  prior  to  release.
However, due to  the large number of equates in the source file,
all possible permutations have NOT been tested, and it should be
understood that revision  4.1  is  experimental  in  nature, and
should  not  be  placed  on-line  in  remote  applications until
sufficient  time  has elapsed to allow for initial  bug  reports
from the field.

     The most significant  difference  between  version  4.1 and
version  3.X  concerns  the  ability  of SD to search a range of
drives and/or user areas for a specified  file.  This capability
is patterned after FILEFIND, but is significantly more useful in
that  SD will report the sizes of files matched.    A  new  BDOS
intercept  routine  has been added, which although more involved
than  the FILEFIND method,  is  more  generally  applicable  and
should  run "as-is" on most CP/M systems.  Thus, by using SD-41,
the use of a separate FILEFIND program should be unnecessary.

     The  basic operation of SD is as in previous releases.  You
merely  type   "SD",   followed  by  an  optional  ambiguous  or
unambiguous  filename (as  you  would  with  the  CCP  directory
command).  Omitting  the  filename  (i.e.,  "SD  [CR]"), will be
interpreted  as  "SD *.*".  Similarly, "SD A:" would  imply  "SD
A:*.*" and "SD B:"  would  imply "SD B:*.*".  In addition to the
filename option, up to 8 command  line options may be specified.
If  options  are  to be specified, then  the  filename  must  be
EXPLICITLY specified  by  at  least a drive code.  Option fields
are  preceded  by a single dollar  sign  as  with  most  Digital
Research programs  such as MAC, and may be essentially free-form
in format.  Example:  SD  A:  $s  a  D  rn u0 fp.  Note that the
reference  to the A drives in "A:" is mandatory.    Invoking  SD
with a command  of the form "SD $s a D rn u0 fp" would result in
SD thinking that  $S was the file to be searched for.  Note also
that spaces and case  within  the option field are insignificant
(i.e., "$ SADrNu0F p" is equivalent  to  "$  S A D R N U0 F P").
The  only  exception concerns the "USER" option  which  will  be
explained later.  Users should also be aware of two restrictions
on the command  line  format.   SD scans the entire command line
for a dollar sign preceded by at  least  1  blank to delimit the
beginning  of  the option field.  For this reason,  invoking  SD
with a command line  such as "SD $ $AR" is illegal since SD will
consider the first dollar sign to be the option field delimiter.
If you need to specify  a  a filename whose first character is a
dollar sign, precede it with  a  drive  code as in "SD A:$ $AR".
In  this  instance,  SD  will  consider  the first  dollar  sign
insignificant as it is not preceded by a blank.



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SD-41 Documentation Notes






     The second restriction is that command  line options may be
specified once and only once per invocation.   That  is,  "SD A:
$SDS"  would be illegal since the "S" option is specified twice.
This shortcoming  is  due  to  the fact that options can be made
into defaults at assembly time.

     The eight options recognized are:

  "S" - system option : system files will be included in
        the output rather than being suppressed.

  "F"  -  file  option : the directory  output  will  be
        echoed to  a  disk  file  named  "SD.DIR" on the
        DEFAULT drive.  If SD.DIR already  exists,  then
        the directory output will be APPENDED to the end
        of  the file.  Otherwise, SD.DIR will be created
        as a new file.  The append feature allows you to
        build  up  one massive file on the default drive
        containing the directories of all of your disks,
        without  having   to  concantenate  a  swarm  of
        individual directory  files.  If you plan to use
        this feature often, it willbe simpler for you to
        have a dedicated version  on  your  MASTCAT disk
        with RESFLG set TRUE.  The advantage  of this is
        that  you  can  work  through  a  pile  of disks
        without  having  to  CTRL-C  or  specify the "R"
        option everytime you SD a new disk.   Failing to
        do  this  will  result in the allocation  vector
        being invalid, and FREE size will be wrong.

  "U" - user option : allows  the  specification  of the
        user  number for the directory of the form "Uxx"
        where the  user  #  is  greater  than 0, but not
        greater than a specified value not to exceed 15.
        The user option specification will be illegal if
        the user # is out of range, omitted,  or if U is
        specified  on  a  pre-CP/M 2 system.  Note  that
        since  the  user  option  requires  a  parameter
        (i.e., the user number),  the  user  number must
        immediately follow the "U" option on the command
        field.    That is, "U1" is legal, but "U  1"  is
        not.  In this respect, the U option differs from
        the other options  in  that  embedded spaces ARE
        significant.

  "A" - all users : causes SD to display  directories of
        all  user  areas  starting  at  the  user   area
        specified  in  the  U  option or, if U option is
        omitted, the default user area and continuing up
        to MAXUSR.

  "R" - reset option : allows for automatic resetting of
        the disk prior to performing directory search so
        that  the  allocation vector  will  be  updated.
        Same as doing  a CTRL-C when changing disks, but
        handy if you didn't  (such  as  when  running  a


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SD-41 Documentation Notes






        SUBMIT  file).  Note that the RESFLG equate will
        force the  R option unconditionally each time SD
        is run.  Useful  for SDing a stack of disks with
        the "F" option, but  slows  down SD considerably
        in normal use.

  "N"  - no page option : unconditionally  disables  the
        page  pause  option.   Useful when running SD in
        the "F" and/or "A" modes when you don't want the
        page prompt slowing you  down.   Note that SD-41
        will  not  put  the page-pause prompt  into  the
        output file.

  "P" - printer option : forces all console output to be
        echoed to the CP/M  list  device,  with the most
        significant bit set to 0.

  "D" - all disk option : allows SD to search  all  disk
        drives  on-line  starting  with  the  disk drive
        specified  or  implied  with  the  command  line
        filename.    For example, "SD B: $D" will result
        in SD searching  all drives beginning with drive
        B.  "SD *.* $D" will  result in SD searching all
        drives beginning with the  drive  that is logged
        in.

     If   an  unrecognized  option  (or  illegal   user   option
specification) is detected, then the command line will be played
back to the  console  up  to  the  point  where  the  error  was
detected.    However,  if the REPERR option is disabled, then SD
will keep its mouth shut  and  ignore  everything on the command
line  past the illegal field.  In this situation,  an  illegally
specified  user  number  would  default back to the current user
number.  The option of DISABLING  error  reporting  was included
primarily  for systems with hidden doors and secret passageways.
Shooting off  rockets  and  clanging  bells  everytime a holswap
starts  "experimenting" just calls attention to  the  fact  that
there really  IS  something  behind  that  hollow- sounding wall
after all (if you get my drift).

     As an added convenience, it is possible to "hard-wire" some
or all of the command line options.  For example, if you want SD
to ALWAYS perform a reset of the disk system  before putting its
show  on the road, you can do just that.  For details,  see  the
comments   preceding  the  option  field  lookup  table  in  the
assembler source file.

     Finally,  if  the  all-disk  and/or  all-user  options  are
enabled,   it  may  be  desirable  to  restrict  searches.    To
facilitate this,  a  table is included in SD (beginning at label
"LODRV" and continuing  through "HIDRV").  The table consists of
a single byte for each drive  to  be  searched beginning with A.
Each byte may be in the range of 0-15 mod  15  and  defines  the
highest  user  number  that  SD  will search for that particular
drive.  The highest drive number to  search  is  defined  by the
length of the table.  If four DBs are present between LODRV  and


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SD-41 Documentation Notes






HIDRV,  then  drives  A-D  can  be  searched.    The source file
includes the LODRV-HIDRV table in its maximum configuration  for
16  drives.    However,  it  is  recommended that you delete DBs
referencing  drives  that  aren't  available   on  your  system.
Although  SD  will  intercept  attempts  to  search non-existant
drives, there really isn't any point in allowing  SD  to  always
search  drive  C  when  you  only  have  2  logical  drives; and
depending  on  how  your  BIOS  is  constructed and how long  it
monkeys around before advising the BDOS  of the select error, it
could save some time.


               A THOUGHT FROM "THE LAST REVISOR"

     If you sit down and figure out the number  of  permutations
of  options  and  equates  in the latest versions of SD,  you'll
understand why there aren't  any warranties as to the absence of
entomological cybernoids.  I leave  it  to the CP/M community to
smoke  out  what bugs may pop-up when a certain  combination  of
variables occurs.    If  you  find  any  bugs,  please  leave an
advisory or a fix on either TCBBS or the Hyde Park RCP/M so that
they can be exterminated.

     Finally, my latest revisions expanded the size of the  load
module considerably, and it is now weighing in at just under  2K
if all of the options are enabled.  A program of this type has a
tendency  to be widely propogated throughout a disk library, and
since 2K is  the  block  size  of  most  double and quad-density
systems, I feel that it is important to try and keep SD under 2K
if at all possible.  That's why some of my  code  may be cryptic
in some places - I've sacrified clarity for code reductions.  If
you  plan  to make public-domain enhancements to SD which  would
push it over  the  2K mark, ask yourself whether its worth tying
up an additional disk  block.    This  is also an invitation for
someone less lazy than myself to further  optimize  the  code to
reduce SD to as compact a package as possible (thus making  room
for more enhancements).  For my part, I quit when I got it under
2K.    It  works,  it  fits and I'm ready to move onto something
else.


                       I pass the torch.

                          David Boruff
                      Knoxville, Tennessee













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SD-41 Documentation Notes