Ceci est le fichier Info grep.info, produit par Makeinfo version 4.0 à
partir grep.texi.
START-INFO-DIR-ENTRY
* grep: (grep). print lines matching a pattern.
END-INFO-DIR-ENTRY
This file documents `grep', a pattern matching engine.
Published by the Free Software Foundation, 59 Temple Place - Suite
330 Boston, MA 02111-1307, USA
Copyright 2000 Free Software Foundation, Inc.
Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.
Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided that
the entire resulting derived work is distributed under the terms of a
permission notice identical to this one.
Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions, except that this permission notice may be stated in a
translation approved by the Foundation.
File: grep.info, Node: Top, Next: Introduction, Up: (dir)
Grep
****
`grep' searches for lines matching a pattern.
This document was produced for version 2.4.2 of GNU `grep'.
* Menu:
* Introduction:: Introduction.
* Invoking:: Invoking `grep'; description of options.
* Diagnostics:: Exit status returned by `grep'.
* Grep Programs:: `grep' programs.
* Regular Expressions:: Regular Expressions.
* Usage:: Examples.
* Reporting Bugs:: Reporting Bugs.
* Concept Index:: A menu with all the topics in this manual.
* Index:: A menu with all `grep' commands
and command-line options.
File: grep.info, Node: Introduction, Next: Invoking, Prev: Top, Up: Top
Introduction
************
`grep' searches the input files for lines containing a match to a
given pattern list. When it finds a match in a line, it copies the
line to standard output (by default), or does whatever other sort of
output you have requested with options.
Though `grep' expects to do the matching on text, it has no limits
on input line length other than available memory, and it can match
arbitrary characters within a line. If the final byte of an input file
is not a newline, `grep' silently supplies one. Since newline is also
a separator for the list of patterns, there is no way to match newline
characters in a text.
File: grep.info, Node: Invoking, Next: Diagnostics, Prev: Introduction, Up: Top
Invoking `grep'
***************
`grep' comes with a rich set of options from POSIX.2 and GNU
extensions.
`-c'
`--count'
Suppress normal output; instead print a count of matching lines
for each input file. With the `-v', `--invert-match' option,
count non-matching lines.
`-e PATTERN'
`--regexp=PATTERN'
Use PATTERN as the pattern; useful to protect patterns beginning
with a `-'.
`-f FILE'
`--file=FILE'
Obtain patterns from FILE, one per line. The empty file contains
zero patterns, and therefore matches nothing.
`-i'
`--ignore-case'
Ignore case distinctions in both the pattern and the input files.
`-l'
`--files-with-matches'
Suppress normal output; instead print the name of each input file
from which output would normally have been printed. The scanning
of every file will stop on the first match.
`-n'
`--line-number'
Prefix each line of output with the line number within its input
file.
`-q'
`--quiet'
`--silent'
Quiet; suppress normal output. The scanning of every file will
stop on the first match. Also see the `-s' or `--no-messages'
option.
`-s'
`--no-messages'
Suppress error messages about nonexistent or unreadable files.
Portability note: unlike GNU `grep', traditional `grep' did not
conform to POSIX.2, because traditional `grep' lacked a `-q'
option and its `-s' option behaved like GNU `grep''s `-q' option.
Shell scripts intended to be portable to traditional `grep' should
avoid both `-q' and `-s' and should redirect output to `/dev/null'
instead.
`-v'
`--invert-match'
Invert the sense of matching, to select non-matching lines.
`-x'
`--line-regexp'
Select only those matches that exactly match the whole line.
GNU Extensions
==============
`-A NUM'
`--after-context=NUM'
Print NUM lines of trailing context after matching lines.
`-B NUM'
`--before-context=NUM'
Print NUM lines of leading context before matching lines.
`-C NUM'
`--context=[NUM]'
Print NUM lines (default 2) of output context.
`-NUM'
Same as `--context=NUM' lines of leading and trailing context.
However, grep will never print any given line more than once.
`-V'
`--version'
Print the version number of `grep' to the standard output stream.
This version number should be included in all bug reports.
`--help'
Print a usage message briefly summarizing these command-line
options and the bug-reporting address, then exit.
`--binary-files=TYPE'
If the first few bytes of a file indicate that the file contains
binary data, assume that the file is of type TYPE. By default,
TYPE is `binary', and `grep' normally outputs either a one-line
message saying that a binary file matches, or no message if there
is no match. If TYPE is `without-match', `grep' assumes that a
binary file does not match; this is equivalent to the `-I' option.
If TYPE is `text', `grep' processes a binary file as if it were
text; this is equivalent to the `-a' option. _Warning:_
`--binary-files=text' might output binary garbage, which can have
nasty side effects if the output is a terminal and if the terminal
driver interprets some of it as commands.
`-b'
`--byte-offset'
Print the byte offset within the input file before each line of
output. When `grep' runs on MS-DOS or MS-Windows, the printed
byte offsets depend on whether the `-u' (`--unix-byte-offsets')
option is used; see below.
`-d ACTION'
`--directories=ACTION'
If an input file is a directory, use ACTION to process it. By
default, ACTION is `read', which means that directories are read
just as if they were ordinary files (some operating systems and
filesystems disallow this, and will cause `grep' to print error
messages for every directory). If ACTION is `skip', directories
are silently skipped. If ACTION is `recurse', `grep' reads all
files under each directory, recursively; this is equivalent to the
`-r' option.
`-H'
`--with-filename'
Print the filename for each match.
`-h'
`--no-filename'
Suppress the prefixing of filenames on output when multiple files
are searched.
`-L'
`--files-without-match'
Suppress normal output; instead print the name of each input file
from which no output would normally have been printed. The
scanning of every file will stop on the first match.
`-a'
`--text'
Process a binary file as if it were text; this is equivalent to the
`--binary-files=text' option.
`-I'
Process a binary file as if it did not contain matching data; this
is equivalent to the `--binary-files=without-match' option.
`-w'
`--word-regexp'
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.
`-r'
`--recursive'
For each directory mentioned in the command line, read and process
all files in that directory, recursively. This is the same as the
`-d recurse' option.
`-y'
Obsolete synonym for `-i'.
`-U'
`--binary'
Treat the file(s) as binary. By default, under MS-DOS and
MS-Windows, `grep' guesses the file type by looking at the
contents of the first 32kB read from the file. If `grep' decides
the file is a text file, it strips the `CR' characters from the
original file contents (to make regular expressions with `^' and
`$' work correctly). Specifying `-U' overrules this guesswork,
causing all files to be read and passed to the matching mechanism
verbatim; if the file is a text file with `CR/LF' pairs at the end
of each line, this will cause some regular expressions to fail.
This option has no effect on platforms other than MS-DOS and
MS-Windows.
`-u'
`--unix-byte-offsets'
Report Unix-style byte offsets. This switch causes `grep' to
report byte offsets as if the file were Unix style text file,
i.e., the byte offsets ignore the `CR' characters which were
stripped. This will produce results identical to running `grep' on
a Unix machine. This option has no effect unless `-b' option is
also used; it has no effect on platforms other than MS-DOS and
MS-Windows.
`--mmap'
If possible, use the `mmap' system call to read input, instead of
the default `read' system call. In some situations, `--mmap'
yields better performance. However, `--mmap' can cause undefined
behavior (including core dumps) if an input file shrinks while
`grep' is operating, or if an I/O error occurs.
`-Z'
`--null'
Output a zero byte (the ASCII `NUL' character) instead of the
character that normally follows a file name. For example, `grep
-lZ' outputs a zero byte after each file name instead of the usual
newline. This option makes the output unambiguous, even in the
presence of file names containing unusual characters like
newlines. This option can be used with commands like `find
-print0', `perl -0', `sort -z', and `xargs -0' to process
arbitrary file names, even those that contain newline characters.
`-z'
`--null-data'
Treat the input as a set of lines, each terminated by a zero byte
(the ASCII `NUL' character) instead of a newline. Like the `-Z'
or `--null' option, this option can be used with commands like
`sort -z' to process arbitrary file names.
Several additional options control which variant of the `grep'
matching engine is used. *Note Grep Programs::.
Environment Variables
=====================
Grep's behavior is affected by the following environment variables.
`GREP_OPTIONS'
This variable specifies default options to be placed in front of
any explicit options. For example, if `GREP_OPTIONS' is
`--binary-files=without-match --directories=skip', `grep' behaves
as if the two options `--binary-files=without-match' and
`--directories=skip' had been specified before any explicit
options. Option specifications are separated by whitespace. A
backslash escapes the next character, so it can be used to specify
an option containing whitespace or a backslash.
`LC_ALL'
`LC_MESSAGES'
`LANG'
These variables specify the `LC_MESSAGES' locale, which determines
the language that `grep' uses for messages. The locale is
determined by the first of these variables that is set. American
English is used if none of these environment variables are set, or
if the message catalog is not installed, or if `grep' was not
compiled with national language support (NLS).
`LC_ALL'
`LC_CTYPE'
`LANG'
These variables specify the `LC_CTYPE' locale, which determines the
type of characters, e.g., which characters are whitespace. The
locale is determined by the first of these variables that is set.
The POSIX locale is used if none of these environment variables
are set, or if the locale catalog is not installed, or if `grep'
was not compiled with national language support (NLS).
`POSIXLY_CORRECT'
If set, `grep' behaves as POSIX.2 requires; otherwise, `grep'
behaves more like other GNU programs. POSIX.2 requires that
options that follow file names must be treated as file names; by
default, such options are permuted to the front of the operand
list and are treated as options. Also, POSIX.2 requires that
unrecognized options be diagnosed as "illegal", but since they are
not really against the law the default is to diagnose them as
"invalid". `POSIXLY_CORRECT' also disables
`_N_GNU_nonoption_argv_flags_', described below.
`_N_GNU_nonoption_argv_flags_'
(Here `N' is `grep''s numeric process ID.) If the Ith character
of this environment variable's value is `1', do not consider the
Ith operand of `grep' to be an option, even if it appears to be
one. A shell can put this variable in the environment for each
command it runs, specifying which operands are the results of file
name wildcard expansion and therefore should not be treated as
options. This behavior is available only with the GNU C library,
and only when `POSIXLY_CORRECT' is not set.
File: grep.info, Node: Diagnostics, Next: Grep Programs, Prev: Invoking, Up: Top
Diagnostics
***********
Normally, exit status is 0 if matches were found, and 1 if no matches
were found (the `-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.
File: grep.info, Node: Grep Programs, Next: Regular Expressions, Prev: Diagnostics, Up: Top
`grep' programs
***************
`grep' searches the named input files (or standard input if no files
are named, or the file name `-' is given) for lines containing a match
to the given pattern. By default, `grep' prints the matching lines.
There are three major variants of `grep', controlled by the following
options.
`-G'
`--basic-regexp'
Interpret pattern as a basic regular expression. This is the
default.
`-E'
`--extended-regexp'
Interpret pattern as an extended regular expression.
`-F'
`--fixed-strings'
Interpret pattern as a list of fixed strings, separated by
newlines, any of which is to be matched.
In addition, two variant programs EGREP and FGREP are available.
EGREP is the same as `grep -E'. FGREP is the same as `grep -F'.
File: grep.info, Node: Regular Expressions, Next: Usage, Prev: Grep Programs, Up: Top
Regular Expressions
*******************
A "regular expression" is a pattern that describes a set of strings.
Regular expressions are constructed analogously to arithmetic
expressions, by using various operators to combine smaller expressions.
`grep' understands two different versions of regular expression syntax:
"basic" and "extended". In 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.
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. A list of characters enclosed by `[' and `]' matches any
single character in that list; if the first character of the list is the
caret `^', then it matches any character *not* in the list. For
example, the regular expression `[0123456789]' matches any single digit.
A range of characters may be specified by giving the first and last
characters, separated by a hyphen.
Finally, certain named classes of characters are predefined, as
follows. Their interpretation depends on the `LC_CTYPE' locale; the
interpretation below is that of the POSIX locale, which is the default
if no `LC_CTYPE' locale is specified.
`[:alnum:]'
Alphanumeric characters: `[:alpha:]' and `[:digit:]'.
`[:alpha:]'
Alphabetic characters: `[:lower:]' and `[:upper:]'.
`[:blank:]'
Blank characters: space and tab.
`[:cntrl:]'
Control characters. In ASCII, these characters have octal codes
000 through 037, and 177 (`DEL'). In other character sets, these
are the equivalent characters, if any.
`[:digit:]'
Digits: `0 1 2 3 4 5 6 7 8 9'.
`[:graph:]'
Graphical characters: `[:alnum:]' and `[:punct:]'.
`[:lower:]'
Lower-case letters: `a b c d e f g h i j k l m n o p q r s t u v w
x y z'.
`[:print:]'
Printable characters: `[:alnum:]', `[:punct:]', and space.
`[:punct:]'
Punctuation characters: `! " # $ % & ' ( ) * + , - . / : ; < = > ?
@ [ \ ] ^ _ ` { | } ~'.
`[:space:]'
Space characters: tab, newline, vertical tab, form feed, carriage
return, and space.
`[:upper:]'
Upper-case letters: `A B C D E F G H I J K L M N O P Q R S T U V W
X Y Z'.
`[:xdigit:]'
Hexadecimal digits: `0 1 2 3 4 5 6 7 8 9 A B C D E F a b c d e f'.
For example, `[[:alnum:]]' means `[0-9A-Za-z]', except the latter
depends upon the POSIX locale and the ASCII character encoding, whereas
the former is independent of locale and character set. (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 `]', place it first in the list. Similarly, to
include a literal `^', place it anywhere but first. Finally, to
include a literal `-', place it last.
The period `.' matches any single character. The symbol `\w' is a
synonym for `[[:alnum:]]' and `\W' is a synonym for `[^[:alnum]]'.
The caret `^' and the dollar sign `$' are metacharacters that
respectively match the empty string at the beginning and end of a line.
The symbols `\<' and `\>' respectively match the empty string at the
beginning and end of a word. The symbol `\b' matches the empty string
at the edge of a word, and `\B' matches the empty string provided it's
not at the edge of a word.
A regular expression may be followed by one of several repetition
operators:
`?'
The preceding item is optional and will be matched at most once.
`*'
The preceding item will be matched zero or more times.
`+'
The preceding item will be matched one or more times.
`{N}'
The preceding item is matched exactly N times.
`{N,}'
The preceding item is matched n or more times.
`{N,M}'
The preceding item is matched at least N times, but not more than
M times.
Two regular expressions may be concatenated; the resulting regular
expression matches any string formed by concatenating two substrings
that respectively match the concatenated subexpressions.
Two regular expressions may be joined by the infix operator `|'; the
resulting regular expression matches any string matching either
subexpression.
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.
The backreference `\N', where N is a single digit, matches the
substring previously matched by the Nth parenthesized subexpression of
the regular expression.
In basic regular expressions the metacharacters `?', `+', `{', `|',
`(', and `)' lose their special meaning; instead use the backslashed
versions `\?', `\+', `\{', `\|', `\(', and `\)'.
Traditional `egrep' did not support the `{' metacharacter, and some
`egrep' implementations support `\{' instead, so portable scripts
should avoid `{' in `egrep' patterns and should use `[{]' to match a
literal `{'.
GNU `egrep' attempts to support traditional usage by assuming that
`{' is not special if it would be the start of an invalid interval
specification. For example, the shell command `egrep '{1'' searches
for the two-character string `{1' instead of reporting a syntax error
in the regular expression. POSIX.2 allows this behavior as an
extension, but portable scripts should avoid it.
File: grep.info, Node: Usage, Next: Reporting Bugs, Prev: Regular Expressions, Up: Top
Usage
*****
Here is an example shell command that invokes GNU `grep':
grep -i 'hello.*world' menu.h main.c
This lists all lines in the files `menu.h' and `main.c' that contain
the string `hello' followed by the string `world'; this is because `.*'
matches zero or more characters within a line. *Note Regular
Expressions::. The `-i' option causes `grep' to ignore case, causing
it to match the line `Hello, world!', which it would not otherwise
match. *Note Invoking::, for more details about how to invoke `grep'.
Here are some common questions and answers about `grep' usage.
1. How can I list just the names of matching files?
grep -l 'main' *.c
lists the names of all C files in the current directory whose
contents mention `main'.
2. How do I search directories recursively?
grep -r 'hello' /home/gigi
searches for `hello' in all files under the directory
`/home/gigi'. For more control of which files are searched, use
`find', `grep' and `xargs'. For example, the following command
searches only C files:
find /home/gigi -name '*.c' -print | xargs grep 'hello' /dev/null
3. What if a pattern has a leading `-'?
grep -e '--cut here--' *
searches for all lines matching `--cut here--'. Without `-e',
`grep' would attempt to parse `--cut here--' as a list of options.
4. Suppose I want to search for a whole word, not a part of a word?
grep -w 'hello' *
searches only for instances of `hello' that are entire words; it
does not match `Othello'. For more control, use `\<' and `\>' to
match the start and end of words. For example:
grep 'hello\>' *
searches only for words ending in `hello', so it matches the word
`Othello'.
5. How do I output context around the matching lines?
grep -C 2 'hello' *
prints two lines of context around each matching line.
6. How do I force grep to print the name of the file?
Append `/dev/null':
grep 'eli' /etc/passwd /dev/null
7. Why do people use strange regular expressions on `ps' output?
ps -ef | grep '[c]ron'
If the pattern had been written without the square brackets, it
would have matched not only the `ps' output line for `cron', but
also the `ps' output line for `grep'.
8. Why does `grep' report "Binary file matches"?
If `grep' listed all matching "lines" from a binary file, it would
probably generate output that is not useful, and it might even
muck up your display. So GNU `grep' suppresses output from files
that appear to be binary files. To force GNU `grep' to output
lines even from files that appear to be binary, use the `-a' or
`--binary-files=text' option. To eliminate the "Binary file
matches" messages, use the `-I' or `--binary-files=without-match'
option.
9. Why doesn't `grep -lv' print nonmatching file names?
`grep -lv' lists the names of all files containing one or more
lines that do not match. To list the names of all files that
contain no matching lines, use the `-L' or `--files-without-match'
option.
10. I can do OR with `|', but what about AND?
grep 'paul' /etc/motd | grep 'franc,ois'
finds all lines that contain both `paul' and `franc,ois'.
11. How can I search in both standard input and in files?
Use the special file name `-':
cat /etc/passwd | grep 'alain' - /etc/motd
File: grep.info, Node: Reporting Bugs, Next: Concept Index, Prev: Usage, Up: Top
Reporting bugs
**************
Email bug reports to <bug-gnu-utils@gnu.org>. Be sure to include
the word "grep" somewhere in the "Subject:" field.
Large repetition counts in the `{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 grep to
run out of memory. Backreferences are very slow, and may require
exponential time.
File: grep.info, Node: Concept Index, Next: Index, Prev: Reporting Bugs, Up: Top
Concept Index
*************
This is a general index of all issues discussed in this manual, with
the exception of the `grep' commands and command-line options.
* Menu:
* after context: Invoking.
* alphabetic characters: Regular Expressions.
* alphanumeric characters: Regular Expressions.
* asterisk: Regular Expressions.
* basic regular expressions: Regular Expressions.
* before context: Invoking.
* binary files: Invoking.
* binary files, DOS/Windows: Invoking.
* blank characters: Regular Expressions.
* braces, one argument: Regular Expressions.
* braces, second argument omitted: Regular Expressions.
* braces, two arguments: Regular Expressions.
* Bugs, reporting: Reporting Bugs.
* byte offset: Invoking.
* byte offsets, on DOS/Windows: Invoking.
* case insensitive search: Invoking.
* case insensitive search, obsolete option: Invoking.
* character classes: Regular Expressions.
* character type: Invoking.
* classes of characters: Regular Expressions.
* context: Invoking.
* context lines, after match: Invoking.
* context lines, before match: Invoking.
* control characters: Regular Expressions.
* counting lines: Invoking.
* default options environment variable: Invoking.
* digit characters: Regular Expressions.
* directory search: Invoking.
* DOS byte offsets: Invoking.
* DOS/Windows binary files: Invoking.
* environment variables: Invoking.
* FAQ about grep usage: Usage.
* files which don't match: Invoking.
* graphic characters: Regular Expressions.
* hexadecimal digits: Regular Expressions.
* interval specifications: Regular Expressions.
* invert matching: Invoking.
* language of messages: Invoking.
* line numbering: Invoking.
* lower-case letters: Regular Expressions.
* match sub-expression at most once: Regular Expressions.
* match sub-expression n or more times: Regular Expressions.
* match sub-expression n times: Regular Expressions.
* match sub-expression zero or more times: Regular Expressions.
* match the whole line: Invoking.
* matching basic regular expressions: Grep Programs.
* matching extended regular expressions: Grep Programs.
* matching fixed strings: Grep Programs.
* matching whole words: Invoking.
* memory mapped input: Invoking.
* message language: Invoking.
* names of matching files: Invoking.
* national language support: Invoking.
* NLS: Invoking.
* no filename prefix: Invoking.
* numeric characters: Regular Expressions.
* pattern from file: Invoking.
* pattern list: Invoking.
* plus sign: Regular Expressions.
* print non-matching lines: Invoking.
* printable characters: Regular Expressions.
* punctuation characters: Regular Expressions.
* question mark: Regular Expressions.
* quiet, silent: Invoking.
* recursive search: Invoking.
* regular expressions: Regular Expressions.
* searching directory trees: Invoking.
* Searching for a pattern.: Introduction.
* space characters: Regular Expressions.
* suppress binary data: Invoking.
* suppress error messages: Invoking.
* translation of message language: Invoking.
* upper-case letters: Regular Expressions.
* Usage summary, printing: Invoking.
* Usage, examples: Usage.
* Using grep, Q&A: Usage.
* Version, printing: Invoking.
* whitespace characters: Regular Expressions.
* with filename prefix: Invoking.
* xdigit class: Regular Expressions.
* zero-terminated file names: Invoking.
* zero-terminated lines: Invoking.
File: grep.info, Node: Index, Prev: Concept Index, Up: Top
Index
*****
This is an alphabetical list of all `grep' commands, command-line
options, and environment variables.
* Menu:
* *: Regular Expressions.
* +: Regular Expressions.
* --after-context: Invoking.
* --basic-regexp: Grep Programs.
* --before-context: Invoking.
* --binary: Invoking.
* --binary-files: Invoking.
* --byte-offset: Invoking.
* --context: Invoking.
* --directories: Invoking.
* --extended-regexp: Grep Programs.
* --file: Invoking.
* --files-with-matches: Invoking.
* --files-without-match: Invoking.
* --fixed-strings: Grep Programs.
* --help: Invoking.
* --ignore-case: Invoking.
* --invert-match: Invoking.
* --line-number: Invoking.
* --line-regexp: Invoking.
* --mmap: Invoking.
* --no-filename: Invoking.
* --no-messages: Invoking.
* --null: Invoking.
* --null-data: Invoking.
* --quiet: Invoking.
* --recursive: Invoking.
* --regexp=PATTERN: Invoking.
* --silent: Invoking.
* --text: Invoking.
* --unix-byte-offsets: Invoking.
* --version: Invoking.
* --With-filename: Invoking.
* --word-regexp: Invoking.
* -a: Invoking.
* -A: Invoking.
* -b: Invoking.
* -B: Invoking.
* -C: Invoking.
* -c: Invoking.
* -count: Invoking.
* -d: Invoking.
* -E: Grep Programs.
* -e: Invoking.
* -F: Grep Programs.
* -f: Invoking.
* -G: Grep Programs.
* -h: Invoking.
* -H: Invoking.
* -i: Invoking.
* -L: Invoking.
* -l: Invoking.
* -n: Invoking.
* -NUM: Invoking.
* -q: Invoking.
* -r: Invoking.
* -s: Invoking.
* -u: Invoking.
* -U: Invoking.
* -V: Invoking.
* -v: Invoking.
* -w: Invoking.
* -x: Invoking.
* -y: Invoking.
* -z: Invoking.
* -Z: Invoking.
* ?: Regular Expressions.
* _N_GNU_nonoption_argv_flags_: Invoking.
* alnum: Regular Expressions.
* alpha: Regular Expressions.
* blank: Regular Expressions.
* cntrl: Regular Expressions.
* digit: Regular Expressions.
* graph: Regular Expressions.
* GREP_OPTIONS: Invoking.
* LANG: Invoking.
* LC_ALL: Invoking.
* LC_CTYPE: Invoking.
* LC_MESSAGES: Invoking.
* lower: Regular Expressions.
* POSIXLY_CORRECT: Invoking.
* print: Regular Expressions.
* punct: Regular Expressions.
* space: Regular Expressions.
* upper: Regular Expressions.
* xdigit: Regular Expressions.
* {n,m}: Regular Expressions.
* {n,}: Regular Expressions.
* {n}: Regular Expressions.
Tag Table:
Node: Top1067
Node: Introduction1839
Node: Invoking2566
Node: Diagnostics13206
Node: Grep Programs13571
Node: Regular Expressions14451
Node: Usage20275
Node: Reporting Bugs23876
Node: Concept Index24407
Node: Index29203
End Tag Table