Simtel MSDOS 1992 September

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Text File | 1988-06-15 | 14KB | 350 lines

fgrep 1.62 ---------- "|" denotes items that are new/changed in the recent versions. Purpose ------- Fgrep (Fast GREP) is a small utility that can be used to find strings of characters in ASCII text files. String search capabilities are not extensive (no regular expressions), but fgrep is small and very, very fast. Fgrep is intended to replace DOS's FIND filter with something faster and more flexible. UNIX people: we fully realize that this isn't the grep or fgrep with which you are familiar. We know that the RE in GREP means "regular expressions" and we know that we don't support regular expressions. However, the name serves to point people in the right direction. Please don't write to tell us that this "isn't really grep". Using fgrep ----------- Fgrep's syntax is fgrep [-aceflmopsvwx01] target {file} The -switches are discussed below. The target is the string of characters for which you are searching. It may need to be bracketed by a pair of non-alphanumeric delimiters. The target should be delimited if: -- it contains spaces or tabs -- it begins with a non-alphanumeric character -- it contains the DOS redirection characters < > |. In the last case, the string MUST be delimited by double quotes ("), otherwise DOS will interpret it as redirection. Examples of targets: mov ax /mov ax/ (contains a space) '/7' (begins with non-alphanumeric) "f->x" (contains ">", must use double quotes) It is always OK to delimit a string, even if delimiters are unnecessary. If the target contains DOS redirection characters (<, >, or |), it MUST be delimited with double quotes ("") or DOS will try to perform unwanted redirection. For example: fgrep "a<=b" myfile.pas The string may include one or more "?" wildcards. The ? will match any single non-null character in the file. E.g., "[?i]" will match "[si]", "[di]", etc., but not "[i]". The list of files may include wild cards. Here are some examples of fgrep use: fgrep -c "include foo.c" *.c fgrep abcd? filea.ext fileb.ext filec.ext fgrep -1f 'call fido' a:\masm\*.asm b:*.asm fgrep ax *.asm If no file is specified, input will be taken from standard input, allowing redirection and piping. For example: arc p somefile foo.txt | fgrep somestring will display occurrences of "somestring" in the file archived as foo.txt in somefile.arc. Output ------ Fgrep's default screen output looks like this: **File <filename> [text of lines containing string] **File <filename> [text of lines containing string] | If the "Microsoft" (-M) switch is used, the output is in this | format: | | FILE.EXT(linenum): text | | This format is the standard format used by Microsoft (R) | language products and by its MEGREP. All useful output is sent to the standard output device, so it may be piped to other programs or redirected to file: fgrep target filea | yourprog fgrep target filea > test.txt Error messages and the program logo will appear always appear on the console device, and will never appear in redirected or piped output. Fgrep always returns an errorlevel to the operating system. It will be one of: 0: String not found in any file 1: String found in at least one file 255: Error (file read error or bad parameter) Switches -------- -A is ANSI mode. If you have ANSI.SYS (or equivalent) installed, escape characters (ASCII 27) in displayed text lines can cause odd results. If you use the -A switch, FGREP will substitute an upside-down question mark (¿) for ESC, possibly resulting in cleaner displays. You'll only need this switch if you have ANSI installed and there are ESC characters in the files you're scanning. -C makes the search case sensitive ("String" will not match "string" or "STRING"). Normally, fgrep ignores case. -E specifies that ONLY an errorlevel is to be returned. There will be no display at all. This is equivalent to the combination -s0. -F causes the "**File" header lines to be displayed only for those files that contain the search string. -L adds line numbers to fgrep's output. -M specifies Microsoft (R) output format. See "Output" above. -O specifies a maximum output width. It should be followed by a decimal number from 1 to 255. For example, -O40 causes fgrep to truncate all output to a maximum of 40 characters per line. Do not confuse the "O" (Output) switch with the "0" (zero text) switch. -P pauses on full screen of output -S suppresses the "**File" header lines in the output. -V provides a reVerse or negative search. That is, all lines that do NOT contain the specified string are displayed. This provides a handy way to get rid of lines containing specified text. Suppose, for example, that you have a file containing a list of file names, and you are interested in all files EXCEPT those that contain a '$' in the name (perhaps they are temporary files): fgrep -v "$" filename -W switch indicates that white space (blanks and tabs) is not significant. White space in both the search string and the input file will be ignored. If -w is specified, the wildcard character (?) will match any nonblank character. -X Do not display the logo/copyright. -0 ("0" text lines) suppresses the display of lines of text containing the specified string. Fgrep will skip immediately to the next file when the string is found. Do not confuse this with the "O" (Output width) switch. -1 ("1" text line) specifies that only the first line containing containing the specified string in each file will be displayed. Fgrep will then skip immediately to the next file. "Fast" search algorithm ----------------------- Beginning with version 1.55, a new and faster technique is used for some searches. This algorithm will NOT be used if: | - line numbers or Microsoft (R) format used (-L or -M) - the search is reVerse (-V) - the search is whitespace insensitive (-W) - the target string contains wildcards ("?") For other searches, the new technique is typically 20-40% faster than the old, although we've seen 70% improvements in some cases. One tester reported that fgrep located a string in the last line of a 440K file in 0.97 seconds (IBM AT). The technique has its roots in searching for unusual (less frequently used) characters, so it will make more of a difference searching for "squeeze" (q is a little-used letter) than it will searching for "eat". When fgrep can use the fast technique, input lines are not limited to 500 characters (as they have been with past versions). Notes ----- 1. The -f and -s switches are mutually exclusive. If both are specified, the last one will be effective. 2. If you specify the -e switch, fgrep will stop processing as soon as a nonzero errorlevel is determined. The -e switch is really designed to enable other programs to determine whether or not a specific file contains a specific string in as little time as possible. For example, here's an algorithm that will quickly 'touch' all files that do NOT contain a specified string: for file in (*.*) do fgrep -e string file if errorlevel < 1 then touch file end 3. The -s switch is automatically set when input is taken from standard input. 4. Fgrep optimizes the combination -s0 (suppress headers, no text) to a -e. 5. If you just want to know which files contain a string, use -0; it saves time because the rest of the file (after the first hit) is skipped. The combination -0f is particularly efficient for this as it will simply display a list of files that contain the string. | 6. If any of the -V, -W, -L, or -M switches are used, or if the target contains wildcards, input lines are limited to a maximum | length of 500 characters (if you use a -w search, spaces don't count). Fgrep expects standard text files; binary files will yield weird results. Word processor files may or may not work, depending on how they are formatted. Lines can be terminated by any of CR, LF, or CR+LF. 7. If output is redirected to disk, make sure there is enough space available. The program does not check. Version 1.62 ------------ Added -M switch. Increased max length of lines ("slow" search) from 256 to 500. Version 1.61 ------------ Fixed a problem with pausing on > 255 hits (-P not specified). Version 1.60 ------------ Added -P switch. Fixed a problem with tab characters and -O switch. Version 1.59 ------------ Added -O switch. Altered -L operations to allow for line numbers > 65535. Line numbers now right justified in a 6-character field. Version 1.58 ------------ Fixed two problems that were causing endless loops in 1.55-1.57. Added -A switch. Version 1.57 ------------ Added -X switch. Versions 1.55/1.56 ----------------- "Fast" search algorithm added (thanks to Dave Angel for the idea and the shove). Fixed problems with redirected input. Forced -v (reVerse) search to show blank lines. Versions 1.50/1.51 ------------------ These versions contain no new features but are significantly faster than earlier versions. Standard (case-insensitive) searches run about 40% faster than 1.45 (which was 25-30% faster than 1.40). "Literal" searches (case-sensitive and spacing-sensitive) are highly optimized and may be as much as 70% faster than 1.45. Version 1.45 ------------ We found a few areas that could be made more efficient. This version can be as much as 25-30% faster than version 1.40. The -L (line numbers) option was added, and improvements made to parameter parsing such that delimiters are not always necessary. Copyright/License/Warranty -------------------------- This document and the program file FGREP.COM ("the software") are copyrighted by the author. The copyright owner hereby licenses you to: use the software; make as many copies of the program and documentation as you wish; give such copies to anyone; and distribute the software and documentation via electronic means. There is no charge for any of the above. However, you are specifically prohibited from charging, or requesting donations, for any such copies, however made; and from distributing the software and/or documentation with commercial products without prior permission. An exception is granted to not-for-profit user's groups, which are authorized to charge a small fee (not to exceed $7) for materials, handling, postage, and general overhead. NO FOR-PROFIT ORGANIZATION IS AUTHORIZED TO CHARGE ANY AMOUNT FOR DISTRIBUTION OF COPIES OF THE SOFTWARE OR DOCUMENTATION, OR TO INCLUDE COPIES OF THE SOFTWARE OR DOCUMENTATION WITH SALES OF THEIR OWN PRODUCTS. THIS INCLUDES A SPECIFIC PROHIBITION AGAINST FOR-PROFIT ORGANIZATIONS DISTRIBUTING THE SOFTWARE, EITHER ALONE OR WITH OTHER SOFTWARE, AND CHARGING A "HANDLING" OR "MATERIALS" FEE OR ANY OTHER SUCH FEE FOR THE DISTRIBUTION. NO FOR-PROFIT ORGANIZATION IS AUTHORIZED TO INCLUDE THE SOFTWARE ON ANY MEDIA FOR WHICH MONEY IS CHARGED. PERIOD. No copy of the software may be distributed or given away without this document; and this notice must not be removed. There is no warranty of any kind, and the copyright owner is not liable for damages of any kind. By using this free software, you agree to this. The software and documentation are: Copyright (C) 1985-1988 by The Cove Software Group Christopher J. Dunford P.O. 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