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pcregrep(1) [redhat man page]

PCREGREP(1)						      General Commands Manual						       PCREGREP(1)

NAME
pcregrep - a grep with Perl-compatible regular expressions. SYNOPSIS
pcregrep [-Vcfhilnrsvx] pattern [file] ... DESCRIPTION
pcregrep searches files for character patterns, in the same way as other grep commands do, but it uses the PCRE regular expression library to support patterns that are compatible with the regular expressions of Perl 5. See pcre(3) for a full description of syntax and semantics. If no files are specified, pcregrep reads the standard input. By default, each line that matches the pattern is copied to the standard out- put, and if there is more than one file, the file name is printed before each line of output. However, there are options that can change how pcregrep behaves. Lines are limited to BUFSIZ characters. BUFSIZ is defined in <stdio.h>. The newline character is removed from the end of each line before it is matched against the pattern. OPTIONS
-V Write the version number of the PCRE library being used to the standard error stream. -c Do not print individual lines; instead just print a count of the number of lines that would otherwise have been printed. If sev- eral files are given, a count is printed for each of them. -ffilename Read patterns from the file, one per line, and match all patterns against each line. There is a maximum of 100 patterns. Trailing white space is removed, and blank lines are ignored. An empty file contains no patterns and therefore matches nothing. -h Suppress printing of filenames when searching multiple files. -i Ignore upper/lower case distinctions during comparisons. -l Instead of printing lines from the files, just print the names of the files containing lines that would have been printed. Each file name is printed once, on a separate line. -n Precede each line by its line number in the file. -r If any file is a directory, recursively scan the files it contains. Without -r a directory is scanned as a normal file. -s Work silently, that is, display nothing except error messages. The exit status indicates whether any matches were found. -v Invert the sense of the match, so that lines which do not match the pattern are now the ones that are found. -x Force the pattern to be anchored (it must start matching at the beginning of the line) and in addition, require it to match the entire line. This is equivalent to having ^ and $ characters at the start and end of each alternative branch in the regular expression. SEE ALSO
pcre(3), Perl 5 documentation DIAGNOSTICS
Exit status is 0 if any matches were found, 1 if no matches were found, and 2 for syntax errors or inacessible files (even if matches were found). AUTHOR
Philip Hazel <ph10@cam.ac.uk> Last updated: 15 August 2001 Copyright (c) 1997-2001 University of Cambridge. PCREGREP(1)

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GREP(1) 						      General Commands Manual							   GREP(1)

NAME
grep, egrep, fgrep - search a file for a pattern SYNOPSIS
grep [ option ] ... expression [ file ] ... egrep [ option ] ... [ expression ] [ file ] ... fgrep [ option ] ... [ strings ] [ file ] DESCRIPTION
Commands of the grep family search the input files (standard input default) for lines matching a pattern. Normally, each line found is copied to the standard output. Grep patterns are limited regular expressions in the style of ex(1); it uses a compact nondeterministic algorithm. Egrep patterns are full regular expressions; it uses a fast deterministic algorithm that sometimes needs exponential space. Fgrep patterns are fixed strings; it is fast and compact. The following options are recognized. -v All lines but those matching are printed. -x (Exact) only lines matched in their entirety are printed (fgrep only). -c Only a count of matching lines is printed. -l The names of files with matching lines are listed (once) separated by newlines. -n Each line is preceded by its relative line number in the file. -b Each line is preceded by the block number on which it was found. This is sometimes useful in locating disk block numbers by con- text. -i The case of letters is ignored in making comparisons -- that is, upper and lower case are considered identical. This applies to grep and fgrep only. -s Silent mode. Nothing is printed (except error messages). This is useful for checking the error status. -w The expression is searched for as a word (as if surrounded by `<' and `>', see ex(1).) (grep only) -e expression Same as a simple expression argument, but useful when the expression begins with a -. -f file The regular expression (egrep) or string list (fgrep) is taken from the file. In all cases the file name is shown if there is more than one input file. Care should be taken when using the characters $ * [ ^ | ( ) and in the expression as they are also meaningful to the Shell. It is safest to enclose the entire expression argument in single quotes ' '. Fgrep searches for lines that contain one of the (newline-separated) strings. Egrep accepts extended regular expressions. In the following description `character' excludes newline: A followed by a single character other than newline matches that character. The character ^ matches the beginning of a line. The character $ matches the end of a line. A . (period) matches any character. A single character not otherwise endowed with special meaning matches that character. A string enclosed in brackets [] matches any single character from the string. Ranges of ASCII character codes may be abbreviated as in `a-z0-9'. A ] may occur only as the first character of the string. A literal - must be placed where it can't be mistaken as a range indicator. A regular expression followed by an * (asterisk) matches a sequence of 0 or more matches of the regular expression. A regular expression followed by a + (plus) matches a sequence of 1 or more matches of the regular expression. A regular expression followed by a ? (question mark) matches a sequence of 0 or 1 matches of the regular expression. Two regular expressions concatenated match a match of the first followed by a match of the second. Two regular expressions separated by | or newline match either a match for the first or a match for the second. A regular expression enclosed in parentheses matches a match for the regular expression. The order of precedence of operators at the same parenthesis level is [] then *+? then concatenation then | and newline. Ideally there should be only one grep, but we don't know a single algorithm that spans a wide enough range of space-time tradeoffs. SEE ALSO
ex(1), sed(1), sh(1) DIAGNOSTICS
Exit status is 0 if any matches are found, 1 if none, 2 for syntax errors or inaccessible files. BUGS
Lines are limited to 256 characters; longer lines are truncated. 4th Berkeley Distribution April 29, 1985 GREP(1)
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