grep(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | REGULAR EXPRESSIONS | EXIT STATUS | ENVIRONMENT | NOTES | COPYRIGHT | BUGS | EXAMPLE | SEE ALSO | COLOPHON

GREP(1)                       User Commands                      GREP(1)

NAME         top

       grep - print lines that match patterns

SYNOPSIS         top

       grep [OPTION...] PATTERNS [FILE...]
       grep [OPTION...] -e PATTERNS ... [FILE...]
       grep [OPTION...] -f PATTERN_FILE ... [FILE...]

DESCRIPTION         top

       grep searches for PATTERNS in each FILE.  PATTERNS is one or more
       patterns separated by newline characters, and grep prints each
       line that matches a pattern.  Typically PATTERNS should be quoted
       when grep is used in a shell command.

       A FILE of “-” stands for standard input.  If no FILE is given,
       recursive searches examine the working directory, and
       nonrecursive searches read standard input.

OPTIONS         top

   Generic Program Information
       --help Output a usage message and exit.

       -V, --version
              Output the version number of grep and exit.

   Pattern Syntax
       -E, --extended-regexp
              Interpret PATTERNS as extended regular expressions (EREs,
              see below).

       -F, --fixed-strings
              Interpret PATTERNS as fixed strings, not regular
              expressions.

       -G, --basic-regexp
              Interpret PATTERNS as basic regular expressions (BREs, see
              below).  This is the default.

       -P, --perl-regexp
              Interpret PATTERNS as Perl-compatible regular expressions
              (PCREs).  This option is experimental when combined with
              the -z (--null-data) option, and grep -P may warn of
              unimplemented features.

   Matching Control
       -e PATTERNS, --regexp=PATTERNS
              Use PATTERNS as the patterns.  If this option is used
              multiple times or is combined with the -f (--file) option,
              search for all patterns given.  This option can be used to
              protect a pattern beginning with “-”.

       -f FILE, --file=FILE
              Obtain patterns from FILE, one per line.  If this option
              is used multiple times or is combined with the -e
              (--regexp) option, search for all patterns given.  The
              empty file contains zero patterns, and therefore matches
              nothing.  If FILE is - , read patterns from standard
              input.

       -i, --ignore-case
              Ignore case distinctions in patterns and input data, so
              that characters that differ only in case match each other.

       --no-ignore-case
              Do not ignore case distinctions in patterns and input
              data.  This is the default.  This option is useful for
              passing to shell scripts that already use -i, to cancel
              its effects because the two options override each other.

       -v, --invert-match
              Invert the sense of matching, to select non-matching
              lines.

       -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.  This option has no
              effect if -x is also specified.

       -x, --line-regexp
              Select only those matches that exactly match the whole
              line.  For a regular expression pattern, this is like
              parenthesizing the pattern and then surrounding it with ^
              and $.

   General Output Control
       -c, --count
              Suppress normal output; instead print a count of matching
              lines for each input file.  With the -v, --invert-match
              option (see above), count non-matching lines.

       --color[=WHEN], --colour[=WHEN]
              Surround the matched (non-empty) strings, matching lines,
              context lines, file names, line numbers, byte offsets, and
              separators (for fields and groups of context lines) with
              escape sequences to display them in color on the terminal.
              The colors are defined by the environment variable
              GREP_COLORS.  WHEN is never, always, or auto.

       -L, --files-without-match
              Suppress normal output; instead print the name of each
              input file from which no output would normally have been
              printed.

       -l, --files-with-matches
              Suppress normal output; instead print the name of each
              input file from which output would normally have been
              printed.  Scanning each input file stops upon first match.

       -m NUM, --max-count=NUM
              Stop reading a file after NUM matching lines.  If NUM is
              zero, grep stops right away without reading input.  A NUM
              of -1 is treated as infinity and grep does not stop; this
              is the default.  If the input is standard input from a
              regular file, and NUM matching lines are output, grep
              ensures that the standard input is positioned to just
              after the last matching line before exiting, regardless of
              the presence of trailing context lines.  This enables a
              calling process to resume a search.  When grep stops after
              NUM matching lines, it outputs any trailing context lines.
              When the -c or --count option is also used, grep does not
              output a count greater than NUM.  When the -v or
              --invert-match option is also used, grep stops after
              outputting NUM non-matching lines.

       -o, --only-matching
              Print only the matched (non-empty) parts of a matching
              line, with each such part on a separate output line.

       -q, --quiet, --silent
              Quiet; do not write anything to standard output.  Exit
              immediately with zero status if any match is found, even
              if an error was detected.  Also see the -s or
              --no-messages option.

       -s, --no-messages
              Suppress error messages about nonexistent or unreadable
              files.

   Output Line Prefix Control
       -b, --byte-offset
              Print the 0-based byte offset within the input file before
              each line of output.  If -o (--only-matching) is
              specified, print the offset of the matching part itself.

       -H, --with-filename
              Print the file name for each match.  This is the default
              when there is more than one file to search.  This is a GNU
              extension.

       -h, --no-filename
              Suppress the prefixing of file names on output.  This is
              the default when there is only one file (or only standard
              input) to search.

       --label=LABEL
              Display input actually coming from standard input as input
              coming from file LABEL.  This can be useful for commands
              that transform a file's contents before searching, e.g.,
              gzip -cd foo.gz | grep --label=foo -H 'some pattern'.  See
              also the -H option.

       -n, --line-number
              Prefix each line of output with the 1-based line number
              within its input file.

       -T, --initial-tab
              Make sure that the first character of actual line content
              lies on a tab stop, so that the alignment of tabs looks
              normal.  This is useful with options that prefix their
              output to the actual content: -H,-n, and -b.  In order to
              improve the probability that lines from a single file will
              all start at the same column, this also causes the line
              number and byte offset (if present) to be printed in a
              minimum size field width.

       -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.

   Context Line Control
       -A NUM, --after-context=NUM
              Print NUM lines of trailing context after matching lines.
              Places a line containing a group separator (--) between
              contiguous groups of matches.  With the -o or
              --only-matching option, this has no effect and a warning
              is given.

       -B NUM, --before-context=NUM
              Print NUM lines of leading context before matching lines.
              Places a line containing a group separator (--) between
              contiguous groups of matches.  With the -o or
              --only-matching option, this has no effect and a warning
              is given.

       -C NUM, -NUM, --context=NUM
              Print NUM lines of output context.  Places a line
              containing a group separator (--) between contiguous
              groups of matches.  With the -o or --only-matching option,
              this has no effect and a warning is given.

       --group-separator=SEP
              When -A, -B, or -C are in use, print SEP instead of --
              between groups of lines.

       --no-group-separator
              When -A, -B, or -C are in use, do not print a separator
              between groups of lines.

   File and Directory Selection
       -a, --text
              Process a binary file as if it were text; this is
              equivalent to the --binary-files=text option.

       --binary-files=TYPE
              If a file's data or metadata indicate that the file
              contains binary data, assume that the file is of type
              TYPE.  Non-text bytes indicate binary data; these are
              either output bytes that are improperly encoded for the
              current locale, or null input bytes when the -z option is
              not given.

              By default, TYPE is binary, and grep suppresses output
              after null input binary data is discovered, and suppresses
              output lines that contain improperly encoded data.  When
              some output is suppressed, grep follows any output with a
              message to standard error saying that a binary file
              matches.

              If TYPE is without-match, when grep discovers null input
              binary data it assumes that the rest of the 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.

              When type is binary, grep may treat non-text bytes as line
              terminators even without the -z option.  This means
              choosing binary versus text can affect whether a pattern
              matches a file.  For example, when type is binary the
              pattern q$ might match q immediately followed by a null
              byte, even though this is not matched when type is text.
              Conversely, when type is binary the pattern . (period)
              might not match a null byte.

              Warning: The -a option 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.  On the other hand, when reading files whose
              text encodings are unknown, it can be helpful to use -a or
              to set LC_ALL='C' in the environment, in order to find
              more matches even if the matches are unsafe for direct
              display.

       -D ACTION, --devices=ACTION
              If an input file is a device, FIFO or socket, use ACTION
              to process it.  By default, ACTION is read, which means
              that devices are read just as if they were ordinary files.
              If ACTION is skip, devices are silently skipped.

       -d ACTION, --directories=ACTION
              If an input file is a directory, use ACTION to process it.
              By default, ACTION is read, i.e., read directories just as
              if they were ordinary files.  If ACTION is skip, silently
              skip directories.  If ACTION is recurse, read all files
              under each directory, recursively, following symbolic
              links only if they are on the command line.  This is
              equivalent to the -r option.

       --exclude=GLOB
              Skip any command-line file with a name suffix that matches
              the pattern GLOB, using wildcard matching; a name suffix
              is either the whole name, or a trailing part that starts
              with a non-slash character immediately after a slash (/)
              in the name.  When searching recursively, skip any subfile
              whose base name matches GLOB; the base name is the part
              after the last slash.  A pattern can use *, ?, and [...]
              as wildcards, and \ to quote a wildcard or backslash
              character literally.

       --exclude-from=FILE
              Skip files whose base name matches any of the file-name
              globs read from FILE (using wildcard matching as described
              under --exclude).

       --exclude-dir=GLOB
              Skip any command-line directory with a name suffix that
              matches the pattern GLOB.  When searching recursively,
              skip any subdirectory whose base name matches GLOB.
              Ignore any redundant trailing slashes in GLOB.

       -I     Process a binary file as if it did not contain matching
              data; this is equivalent to the
              --binary-files=without-match option.

       --include=GLOB
              Search only files whose base name matches GLOB (using
              wildcard matching as described under --exclude).  If
              contradictory --include and --exclude options are given,
              the last matching one wins.  If no --include or --exclude
              options match, a file is included unless the first such
              option is --include.

       -r, --recursive
              Read all files under each directory, recursively,
              following symbolic links only if they are on the command
              line.  Note that if no file operand is given, grep
              searches the working directory.  This is equivalent to the
              -d recurse option.

       -R, --dereference-recursive
              Read all files under each directory, recursively.  Follow
              all symbolic links, unlike -r.

   Other Options
       --line-buffered
              Use line buffering on output.  This can cause a
              performance penalty.

       -U, --binary
              Treat the file(s) as binary.  By default, under MS-DOS and
              MS-Windows, grep guesses whether a file is text or binary
              as described for the --binary-files option.  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.

       -z, --null-data
              Treat input and output data as sequences 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.

REGULAR EXPRESSIONS         top

       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 three different versions of regular expression
       syntax: “basic” (BRE), “extended” (ERE) and “perl” (PCRE).  In
       GNU grep, basic and extended regular expressions are merely
       different notations for the same pattern-matching functionality.
       In other implementations, basic regular expressions are
       ordinarily less powerful than extended, though occasionally it is
       the other way around.  The following description applies to
       extended regular expressions; differences for basic regular
       expressions are summarized afterwards.  Perl-compatible regular
       expressions have different functionality, and are documented in
       pcre2syntax(3) and pcre2pattern(3), but work only if PCRE support
       is enabled.

       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
       meta-character with special meaning may be quoted by preceding it
       with a backslash.

       The period . matches any single character.  It is unspecified
       whether it matches an encoding error.

   Character Classes and Bracket Expressions
       A bracket expression is a list of characters enclosed by [ and ].
       It 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; it is unspecified whether it matches
       an encoding error.  For example, the regular expression
       [0123456789] matches any single digit.

       Within a bracket expression, a range expression consists of two
       characters separated by a hyphen.  It matches any single
       character that sorts between the two characters, inclusive, using
       the locale's collating sequence and character set.  For example,
       in the default C locale, [a-d] is equivalent to [abcd].  Many
       locales sort characters in dictionary order, and in these locales
       [a-d] is typically not equivalent to [abcd]; it might be
       equivalent to [aBbCcDd], for example.  To obtain the traditional
       interpretation of bracket expressions, you can use the C locale
       by setting the LC_ALL environment variable to the value C.

       Finally, certain named classes of characters are predefined
       within bracket expressions, as follows.  Their names are self
       explanatory, and they are [:alnum:], [:alpha:], [:blank:],
       [:cntrl:], [:digit:], [:graph:], [:lower:], [:print:], [:punct:],
       [:space:], [:upper:], and [:xdigit:].  For example, [[:alnum:]]
       means the character class of numbers and letters in the current
       locale.  In the C locale and ASCII character set encoding, this
       is the same as [0-9A-Za-z].  (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 expression.)
       Most meta-characters lose their special meaning inside bracket
       expressions.  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.

   Anchoring
       The caret ^ and the dollar sign $ are meta-characters that
       respectively match the empty string at the beginning and end of a
       line.

   The Backslash Character and Special Expressions
       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.  The symbol \w is a
       synonym for [_[:alnum:]] and \W is a synonym for [^_[:alnum:]].

   Repetition
       A regular expression may be followed by one of several repetition
       operators:
       ?      The preceding item is optional and 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.
       {,m}   The preceding item is matched at most m times.  This is a
              GNU extension.
       {n,m}  The preceding item is matched at least n times, but not
              more than m times.

   Concatenation
       Two regular expressions may be concatenated; the resulting
       regular expression matches any string formed by concatenating two
       substrings that respectively match the concatenated expressions.

   Alternation
       Two regular expressions may be joined by the infix operator |;
       the resulting regular expression matches any string matching
       either alternate expression.

   Precedence
       Repetition takes precedence over concatenation, which in turn
       takes precedence over alternation.  A whole expression may be
       enclosed in parentheses to override these precedence rules and
       form a subexpression.

   Back-references and Subexpressions
       The back-reference \n, where n is a single digit, matches the
       substring previously matched by the nth parenthesized
       subexpression of the regular expression.

   Basic vs Extended Regular Expressions
       In basic regular expressions the meta-characters ?, +, {, |, (,
       and ) lose their special meaning; instead use the backslashed
       versions \?, \+, \{, \|, \(, and \).

EXIT STATUS         top

       Normally the exit status is 0 if a line is selected, 1 if no
       lines were selected, and 2 if an error occurred.  However, if the
       -q or --quiet or --silent is used and a line is selected, the
       exit status is 0 even if an error occurred.

ENVIRONMENT         top

       The behavior of grep is affected by the following environment
       variables.

       The locale for category LC_foo is specified by examining the
       three environment variables LC_ALL, LC_foo, LANG, in that order.
       The first of these variables that is set specifies the locale.
       For example, if LC_ALL is not set, but LC_MESSAGES is set to
       pt_BR, then the Brazilian Portuguese locale is used for the
       LC_MESSAGES category.  The C locale is used if none of these
       environment variables are set, if the locale catalog is not
       installed, or if grep was not compiled with national language
       support (NLS).  The shell command locale -a lists locales that
       are currently available.

       GREP_COLORS
              Controls how the --color option highlights output.  Its
              value is a colon-separated list of capabilities that
              defaults to
              ms=01;31:mc=01;31:sl=:cx=:fn=35:ln=32:bn=32:se=36 with the
              rv and ne boolean capabilities omitted (i.e., false).
              Supported capabilities are as follows.

              sl=    SGR substring for whole selected lines (i.e.,
                     matching lines when the -v command-line option is
                     omitted, or non-matching lines when -v is
                     specified).  If however the boolean rv capability
                     and the -v command-line option are both specified,
                     it applies to context matching lines instead.  The
                     default is empty (i.e., the terminal's default
                     color pair).

              cx=    SGR substring for whole context lines (i.e., non-
                     matching lines when the -v command-line option is
                     omitted, or matching lines when -v is specified).
                     If however the boolean rv capability and the -v
                     command-line option are both specified, it applies
                     to selected non-matching lines instead.  The
                     default is empty (i.e., the terminal's default
                     color pair).

              rv     Boolean value that reverses (swaps) the meanings of
                     the sl= and cx= capabilities when the -v command-
                     line option is specified.  The default is false
                     (i.e., the capability is omitted).

              mt=01;31
                     SGR substring for matching non-empty text in any
                     matching line (i.e., a selected line when the -v
                     command-line option is omitted, or a context line
                     when -v is specified).  Setting this is equivalent
                     to setting both ms= and mc= at once to the same
                     value.  The default is a bold red text foreground
                     over the current line background.

              ms=01;31
                     SGR substring for matching non-empty text in a
                     selected line.  (This is only used when the -v
                     command-line option is omitted.)  The effect of the
                     sl= (or cx= if rv) capability remains active when
                     this kicks in.  The default is a bold red text
                     foreground over the current line background.

              mc=01;31
                     SGR substring for matching non-empty text in a
                     context line.  (This is only used when the -v
                     command-line option is specified.)  The effect of
                     the cx= (or sl= if rv) capability remains active
                     when this kicks in.  The default is a bold red text
                     foreground over the current line background.

              fn=35  SGR substring for file names prefixing any content
                     line.  The default is a magenta text foreground
                     over the terminal's default background.

              ln=32  SGR substring for line numbers prefixing any
                     content line.  The default is a green text
                     foreground over the terminal's default background.

              bn=32  SGR substring for byte offsets prefixing any
                     content line.  The default is a green text
                     foreground over the terminal's default background.

              se=36  SGR substring for separators that are inserted
                     between selected line fields (:), between context
                     line fields, (-), and between groups of adjacent
                     lines when nonzero context is specified (--).  The
                     default is a cyan text foreground over the
                     terminal's default background.

              ne     Boolean value that prevents clearing to the end of
                     line using Erase in Line (EL) to Right (\33[K) each
                     time a colorized item ends.  This is needed on
                     terminals on which EL is not supported.  It is
                     otherwise useful on terminals for which the
                     back_color_erase (bce) boolean terminfo capability
                     does not apply, when the chosen highlight colors do
                     not affect the background, or when EL is too slow
                     or causes too much flicker.  The default is false
                     (i.e., the capability is omitted).

              Note that boolean capabilities have no =... part.  They
              are omitted (i.e., false) by default and become true when
              specified.

              See the Select Graphic Rendition (SGR) section in the
              documentation of the text terminal that is used for
              permitted values and their meaning as character
              attributes.  These substring values are integers in
              decimal representation and can be concatenated with
              semicolons.  grep takes care of assembling the result into
              a complete SGR sequence (\33[...m).  Common values to
              concatenate include 1 for bold, 4 for underline, 5 for
              blink, 7 for inverse, 39 for default foreground color, 30
              to 37 for foreground colors, 90 to 97 for 16-color mode
              foreground colors, 38;5;0 to 38;5;255 for 88-color and
              256-color modes foreground colors, 49 for default
              background color, 40 to 47 for background colors, 100 to
              107 for 16-color mode background colors, and 48;5;0 to
              48;5;255 for 88-color and 256-color modes background
              colors.

       LC_ALL, LC_COLLATE, LANG
              These variables specify the locale for the LC_COLLATE
              category, which determines the collating sequence used to
              interpret range expressions like [a-z].

       LC_ALL, LC_CTYPE, LANG
              These variables specify the locale for the LC_CTYPE
              category, which determines the type of characters, e.g.,
              which characters are whitespace.  This category also
              determines the character encoding, that is, whether text
              is encoded in UTF-8, ASCII, or some other encoding.  In
              the C or POSIX locale, all characters are encoded as a
              single byte and every byte is a valid character.

       LC_ALL, LC_MESSAGES, LANG
              These variables specify the locale for the LC_MESSAGES
              category, which determines the language that grep uses for
              messages.  The default C locale uses American English
              messages.

       POSIXLY_CORRECT
              If set, grep behaves as POSIX requires; otherwise, grep
              behaves more like other GNU programs.  POSIX 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 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”.

NOTES         top

       This man page is maintained only fitfully; the full documentation
       is often more up-to-date.

COPYRIGHT         top

       Copyright 1998-2000, 2002, 2005-2023 Free Software Foundation,
       Inc.

       This is free software; see the source for copying conditions.
       There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR
       A PARTICULAR PURPOSE.

BUGS         top

   Reporting Bugs
       Email bug reports to the bug-reporting address ⟨bug-
       grep@gnu.org⟩.  An email archive 
       ⟨https://lists.gnu.org/mailman/listinfo/bug-grep⟩ and a bug
       tracker ⟨https://debbugs.gnu.org/cgi/pkgreport.cgi?package=grep⟩
       are available.

   Known Bugs
       Large repetition counts in the {n,m} 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.

       Back-references are very slow, and may require exponential time.

EXAMPLE         top

       The following example outputs the location and contents of any
       line containing “f” and ending in “.c”, within all files in the
       current directory whose names contain “g” and end in “.h”.  The
       -n option outputs line numbers, the -- argument treats expansions
       of “*g*.h” starting with “-” as file names not options, and the
       empty file /dev/null causes file names to be output even if only
       one file name happens to be of the form “*g*.h”.

         $ grep -n -- 'f.*\.c$' *g*.h /dev/null
         argmatch.h:1:/* definitions and prototypes for argmatch.c

       The only line that matches is line 1 of argmatch.h.  Note that
       the regular expression syntax used in the pattern differs from
       the globbing syntax that the shell uses to match file names.

SEE ALSO         top

   Regular Manual Pages
       awk(1), cmp(1), diff(1), find(1), perl(1), sed(1), sort(1),
       xargs(1), read(2), pcre2(3), pcre2syntax(3), pcre2pattern(3),
       terminfo(5), glob(7), regex(7)

   Full Documentation
       A complete manual ⟨https://www.gnu.org/software/grep/manual/⟩ is
       available.  If the info and grep programs are properly installed
       at your site, the command

              info grep

       should give you access to the complete manual.

COLOPHON         top

       This page is part of the GNU grep (regular expression file search
       tool) project.  Information about the project can be found at 
       ⟨https://www.gnu.org/software/grep/⟩.  If you have a bug report
       for this manual page, send it to bug-grep@gnu.org.  This page was
       obtained from the project's upstream Git repository
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GNU grep 3.11.21-102b-dirty    2019-12-29                        GREP(1)

Pages that refer to this page: look(1)pmrep(1)sed(1)regex(3)regex(7)bridge(8)ip(8)tc(8)