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diff --git a/gnu/grep/grep.1 b/gnu/grep/grep.1 deleted file mode 100644 index 27c6b0e419d2..000000000000 --- a/gnu/grep/grep.1 +++ /dev/null @@ -1,375 +0,0 @@ -.TH GREP 1 "1992 September 10" "GNU Project" -.SH NAME -grep, egrep, fgrep \- print lines matching a pattern -.SH SYNOPOSIS -.B grep -[ -.BR \- [[ AB "] ]\c" -.I "num" -] -[ -.BR \- [ CEFGVBchilnsvwx ] -] -[ -.B \-e -] -.I pattern -| -.BI \-f file -] [ -.I files... -] -.SH DESCRIPTION -.PP -.B Grep -searches the named input -.I files -(or standard input if no files are named, or -the file name -.B \- -is given) -for lines containing a match to the given -.IR pattern . -By default, -.B grep -prints the matching lines. -.PP -There are three major variants of -.BR grep , -controlled by the following options. -.PD 0 -.TP -.B \-G -Interpret -.I pattern -as a basic regular expression (see below). This is the default. -.TP -.B \-E -Interpret -.I pattern -as an extended regular expression (see below). -.TP -.B \-F -Interpret -.I pattern -as a list of fixed strings, separated by newlines, -any of which is to be matched. -.LP -In addition, two variant programs -.B egrep -and -.B fgrep -are available. -.B Egrep -is similiar (but not identical) to -.BR "grep\ \-E" , -and is compatible with the historical Unix -.BR egrep . -.B Fgrep -is the same as -.BR "grep\ \-F" . -.PD -.LP -All variants of -.B grep -understand the following options: -.PD 0 -.TP -.BI \- num -Matches will be printed with -.I num -lines of leading and trailing context. However, -.B grep -will never print any given line more than once. -.TP -.BI \-A " num" -Print -.I num -lines of trailing context after matching lines. -.TP -.BI \-B " num" -Print -.I num -lines of leading context before matching lines. -.TP -.B \-C -Equivalent to -.BR \-2 . -.TP -.B \-V -Print the version number of -.B grep -to standard error. This version number should -be included in all bug reports (see below). -.TP -.B \-b -Print the byte offset within the input file before -each line of output. -.TP -.B \-c -Suppress normal output; instead print a count of -matching lines for each input file. -With the -.B \-v -option (see below), count non-matching lines. -.TP -.BI \-e " pattern" -Use -.I pattern -as the pattern; useful to protect patterns beginning with -.BR \- . -.TP -.BI \-f " file" -Obtain the pattern from -.IR file . -.TP -.B \-h -Suppress the prefixing of filenames on output -when multiple files are searched. -.TP -.B \-i -Ignore case distinctions in both the -.I pattern -and the input files. -.TP -.B \-L -Suppress normal output; instead print the name -of each input file from which no output would -normally have been printed. -.TP -.B \-l -Suppress normal output; instead print -the name of each input file from which output -would normally have been printed. -.TP -.B \-n -Prefix each line of output with the line number -within its input file. -.TP -.B \-q -Quiet; suppress normal output. -.TP -.B \-s -Suppress error messages about nonexistent or unreadable files. -.TP -.B \-v -Invert the sense of matching, to select non-matching lines. -.TP -.B \-w -Select only those lines containing matches that form whole words. -The test is that the matching substring must either be at the -beginning of the line, or preceded by a non-word constituent -character. Similarly, it must be either at the end of the line -or followed by a non-word constituent character. Word-constituent -characters are letters, digits, and the underscore. -.TP -.B \-x -Select only those matches that exactly match the whole line. -.PD -.SH "REGULAR EXPRESSIONS" -.PP -A regular expression is a pattern that describes a set of strings. -Regular expressions are constructed analagously to arithmetic -expressions, by using various operators to combine smaller expressions. -.PP -.B Grep -understands two different versions of regular expression syntax: -``basic'' and ``extended.'' In -.RB "GNU\ " grep , -there is no difference in available functionality using either syntax. -In other implementations, basic regular expressions are less powerful. -The following description applies to extended regular expressions; -differences for basic regular expressions are summarized afterwards. -.PP -The fundamental building blocks are the regular expressions that match -a single character. Most characters, including all letters and digits, -are regular expressions that match themselves. Any metacharacter with -special meaning may be quoted by preceding it with a backslash. -.PP -A list of characters enclosed by -.B [ -and -.B ] -matches any single -character in that list; if the first character of the list -is the caret -.B ^ -then it matches any character -.I not -in the list. -For example, the regular expression -.B [0123456789] -matches any single digit. A range of ASCII characters -may be specified by giving the first and last characters, separated -by a hyphen. -Finally, certain named classes of characters are predefined. -Their names are self explanatory, and they are -.BR [:alnum:] , -.BR [:alpha:] , -.BR [:cntrl:] , -.BR [:digit:] , -.BR [:graph:] , -.BR [:lower:] , -.BR [:print:] , -.BR [:punct:] , -.BR [:space:] , -.BR [:upper:] , -and -.BR [:xdigit:]. -For example, -.B [[:alnum:]] -means -.BR [0-9A-Za-z] , -except the latter form is dependent upon the ASCII character encoding, -whereas the former is portable. -(Note that the brackets in these class names are part of the symbolic -names, and must be included in addition to the brackets delimiting -the bracket list.) Most metacharacters lose their special meaning -inside lists. To include a literal -.B ] -place it first in the list. Similarly, to include a literal -.B ^ -place it anywhere but first. Finally, to include a literal -.B \- -place it last. -.PP -The period -.B . -matches any single character. -The symbol -.B \ew -is a synonym for -.B [[:alnum:]] -and -.B \eW -is a synonym for -.BR [^[:alnum]] . -.PP -The caret -.B ^ -and the dollar sign -.B $ -are metacharacters that respectively match the empty string at the -beginning and end of a line. -The symbols -.B \e< -and -.B \e> -respectively match the empty string at the beginning and end of a word. -The symbol -.B \eb -matches the empty string at the edge of a word, -and -.B \eB -matches the empty string provided it's -.I not -at the edge of a word. -.PP -A regular expression matching a single character may be followed -by one of several repetition operators: -.PD 0 -.TP -.B ? -The preceding item is optional and matched at most once. -.TP -.B * -The preceding item will be matched zero or more times. -.TP -.B + -The preceding item will be matched one or more times. -.TP -.BI { n } -The preceding item is matched exactly -.I n -times. -.TP -.BI { n ,} -The preceding item is matched -.I n -or more times. -.TP -.BI {, m } -The preceding item is optional and is matched at most -.I m -times. -.TP -.BI { n , m } -The preceding item is matched at least -.I n -times, but not more than -.I m -times. -.PD -.PP -Two regular expressions may be concatenated; the resulting -regular expression matches any string formed by concatenating -two substrings that respectively match the concatenated -subexpressions. -.PP -Two regular expressions may be joined by the infix operator -.BR | ; -the resulting regular expression matches any string matching -either subexpression. -.PP -Repetition takes precedence over concatenation, which in turn -takes precedence over alternation. A whole subexpression may be -enclosed in parentheses to override these precedence rules. -.PP -The backreference -.BI \e n\c -\&, where -.I n -is a single digit, matches the substring -previously matched by the -.IR n th -parenthesized subexpression of the regular expression. -.PP -In basic regular expressions the metacharacters -.BR ? , -.BR + , -.BR { , -.BR | , -.BR ( , -and -.BR ) -lose their special meaning; instead use the backslashed -versions -.BR \e? , -.BR \e+ , -.BR \e{ , -.BR \e| , -.BR \e( , -and -.BR \e) . -.PP -In -.B egrep -the metacharacter -.B { -loses its special meaning; instead use -.BR \e{ . -.SH DIAGNOSTICS -.PP -Normally, exit status is 0 if matches were found, -and 1 if no matches were found. (The -.B \-v -option inverts the sense of the exit status.) -Exit status is 2 if there were syntax errors -in the pattern, inaccessible input files, or -other system errors. -.SH BUGS -.PP -Email bug reports to -.BR bug-gnu-utils@prep.ai.mit.edu . -Be sure to include the word ``grep'' somewhere in the ``Subject:'' field. -.PP -Large repetition counts in the -.BI { m , n } -construct may cause grep to use lots of memory. -In addition, -certain other obscure regular expressions require exponential time -and space, and may cause -.B grep -to run out of memory. -.PP -Backreferences are very slow, and may require exponential time. |