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grep(1) [v7 man page]

GREP(1) 						      General Commands Manual							   GREP(1)

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; unless the -h flag is used, the file name is shown if there is more than one input file. Grep patterns are limited regular expressions in the style of ed(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. -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 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. -s No output is produced, only status. -h Do not print filename headers with output lines. -y Lower case letters in the pattern will also match upper case letters in the input (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. -x (Exact) only lines matched in their entirety are printed (fgrep only). 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 matches that character. The character ^ ($) matches the beginning (end) of a line. A . 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 * (+, ?) matches a sequence of 0 or more (1 or more, 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. SEE ALSO
ed(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
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. Lines are limited to 256 characters; longer lines are truncated. GREP(1)

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MATCH(1L)						      Schily's USER COMMANDS							 MATCH(1L)

match - searches for patterns in files SYNOPSIS
match [ -option ] pattern [ file ... ] DESCRIPTION
Match searches the named files or standard input (if no filenames are given) for the occurrences of the given pattern on each line. The program accepts literal characters or special pattern matching characters. All lines that match the pattern are output on standard output. You can only specify one pattern string for each match, however, you can construct an arbitrarily complex string. When you do not specify a file, match can be used as a filter to display desired lines. Standard in is used if no files are specified. OPTIONS
-not, -v Prints all lines that do not match. -i Ignore the case of letters -m Force not to use the magic mode -w Search for pattern as a word -x Display only those lines which match exactly -c Display matching count for each file -l Display name of each file which matches -s Be silent indicate match in exit code -h Do not display filenames -n Precede matching lines with line number (with respect to the input file) -b Precede matching lines with block number REGULAR EXPRESSIONS
The following is a table of all the pattern matching characters: c An ordinary character (not one of the special characters discussed below) is a one character regular expression that matches that character. c A backslash () followed by any special character is a one character regular expression that matches the special character itself. The special characters are: ! # % * { } [ ] ? ^ $ ! Logical OR as in match this!that!the_other. You may have to use `{}' for precedence grouping. # A hash mark followed by any regular expression matches any number (including zero) occurrences of the regular expression. ? Matches exactly any one character. W? matches Wa, Wb, Wc, W1, W2, W3 ... * Matches any number of any character. % Matches exactly nothing. It can be used in groups of ored patterns to specify that an empty alternative is possible. {} Curly brackets may be used to enclose patterns to specify a precedence grouping, and may be nested. {%!{test}}version matches the strings testversion and version. [string] A non empty string of characters enclosed in square brackets is a one character regular expression that matches any one character in that string. If however the first character of the string is a circumflex (^), the one character expression matches any character which is not in the string. The ^ has this special meaning only if it occurs first in the string. The minus (-) may be used to indi- cate a range of consecutive ASCII characters; for example, [0-9] is equivalent to any one of the digits. The - loses it's special meaning if it occurs first (after an initial ^, if any) or last in the string. The right square bracket (]) and the backslash () must be quoted with a backslash if you want to use it within the string. ^ Matches the beginning of a line. $ Matches the end of a line. (^*$ matches any entire line) EXAMPLES
grep(1), fgrep(1), egrep(1) DIAGNOSTICS
Even if a match occurs more than once per line, the line is output only once. Quote special pattern matching characters to prevent them from being expanded by the Command Interpreter. BUGS
The length of the pattern is currently limited to 100 characters. This limit is reduced by 38 if the -w option is used. Joerg Schilling 15. Juli 1988 MATCH(1L)
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