trusty (1) ack-grep.1p.gz

Provided by: ack-grep_2.12-1_all bug

NAME

       ack-grep - grep-like text finder

SYNOPSIS

           ack-grep [options] PATTERN [FILE...]
           ack-grep -f [options] [DIRECTORY...]

DESCRIPTION

       Ack is designed as a replacement for 99% of the uses of grep.

       Ack 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, ack-grep prints the matching lines.

       PATTERN is a Perl regular expression.  Perl regular expressions are commonly found in other programming
       languages, but for the particulars of their behavior, please consult
       <http://perldoc.perl.org/perlreref.html|perlreref>.  If you don't know how to use regular expression but
       are interested in learning, you may consult <http://perldoc.perl.org/perlretut.html|perlretut>.  If you
       do not need or want ack-grep to use regular expressions, please see the "-Q"/"--literal" option.

       Ack can also list files that would be searched, without actually searching them, to let you take
       advantage of ack-grep's file-type filtering capabilities.

FILE SELECTION

       If files are not specified for searching, either on the command line or piped in with the "-x" option,
       ack-grep delves into subdirectories selecting files for searching.

       ack-grep is intelligent about the files it searches.  It knows about certain file types, based on both
       the extension on the file and, in some cases, the contents of the file.  These selections can be made
       with the --type option.

       With no file selection, ack-grep searches through regular files that are not explicitly excluded by
       --ignore-dir and --ignore-file options, either present in ackrc files or on the command line.

       The default options for ack ignore certain files and directories.  These include:

       •   Backup files: Files matching #*# or ending with ~.

       •   Coredumps: Files matching core.\d+

       •   Version control directories like .svn and .git.

       Run ack-grep with the "--dump" option to see what settings are set.

       However, ack-grep always searches the files given on the command line, no matter what type.  If you tell
       ack-grep to search in a coredump, it will search in a coredump.

DIRECTORY SELECTION

       ack-grep descends through the directory tree of the starting directories specified.  If no directories
       are specified, the current working directory is used.  However, it will ignore the shadow directories
       used by many version control systems, and the build directories used by the Perl MakeMaker system.  You
       may add or remove a directory from this list with the --[no]ignore-dir option. The option may be repeated
       to add/remove multiple directories from the ignore list.

       For a complete list of directories that do not get searched, run "ack-grep --dump".

WHEN TO USE GREP

       ack-grep trumps grep as an everyday tool 99% of the time, but don't throw grep away, because there are
       times you'll still need it.

       E.g., searching through huge files looking for regexes that can be expressed with grep syntax should be
       quicker with grep.

       If your script or parent program uses grep "--quiet" or "--silent" or needs exit 2 on IO error, use grep.

OPTIONS

       --ackrc
           Specifies an ackrc file to load after all others; see "ACKRC LOCATION SEMANTICS".

       -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.

       --[no]break
           Print a break between results from different files. On by default when used interactively.

       -C [NUM], --context[=NUM]
           Print NUM lines (default 2) of context around matching lines.

       -c, --count
           Suppress normal output; instead print a count of matching lines for each input file.  If -l is in
           effect, it will only show the number of lines for each file that has lines matching.  Without -l,
           some line counts may be zeroes.

           If combined with -h (--no-filename) ack-grep outputs only one total count.

       --[no]color, --[no]colour
           --color highlights the matching text.  --nocolor suppresses the color.  This is on by default unless
           the output is redirected.

           On Windows, this option is off by default unless the Win32::Console::ANSI module is installed or the
           "ACK_PAGER_COLOR" environment variable is used.

       --color-filename=color
           Sets the color to be used for filenames.

       --color-match=color
           Sets the color to be used for matches.

       --color-lineno=color
           Sets the color to be used for line numbers.

       --[no]column
           Show the column number of the first match.  This is helpful for editors that can place your cursor at
           a given position.

       --create-ackrc
           Dumps the default ack-grep options to standard output.  This is useful for when you want to customize
           the defaults.

       --dump
           Writes the list of options loaded and where they came from to standard output.  Handy for debugging.

       --[no]env
           --noenv disables all environment processing. No .ackrc is read and all environment variables are
           ignored. By default, ack-grep considers .ackrc and settings in the environment.

       --flush
           --flush flushes output immediately.  This is off by default unless ack-grep is running interactively
           (when output goes to a pipe or file).

       -f  Only print the files that would be searched, without actually doing any searching.  PATTERN must not
           be specified, or it will be taken as a path to search.

       --files-from=FILE
           The list of files to be searched is specified in FILE.  The list of files are separated by newlines.
           If FILE is "-", the list is loaded from standard input.

       --[no]filter
           Forces ack-grep to act as if it were receiving input via a pipe.

       --[no]follow
           Follow or don't follow symlinks, other than whatever starting files or directories were specified on
           the command line.

           This is off by default.

       -g PATTERN
           Print files where the relative path + filename matches PATTERN.  This option can be combined with
           --color to make it easier to spot the match.

       --[no]group
           --group groups matches by file name.  This is the default when used interactively.

           --nogroup prints one result per line, like grep.  This is the default when output is redirected.

       -H, --with-filename
           Print the filename for each match. This is the default unless searching a single explicitly specified
           file.

       -h, --no-filename
           Suppress the prefixing of filenames on output when multiple files are searched.

       --[no]heading
           Print a filename heading above each file's results.  This is the default when used interactively.

       --help, -?
           Print a short help statement.

       --help-types, --help=types
           Print all known types.

       -i, --ignore-case
           Ignore case distinctions in PATTERN

       --ignore-ack-defaults
           Tells ack-grep to completely ignore the default definitions provided with ack-grep.  This is useful
           in combination with --create-ackrc if you really want to customize ack-grep.

       --[no]ignore-dir=DIRNAME, --[no]ignore-directory=DIRNAME
           Ignore directory (as CVS, .svn, etc are ignored). May be used multiple times to ignore multiple
           directories. For example, mason users may wish to include --ignore-dir=data. The --noignore-dir
           option allows users to search directories which would normally be ignored (perhaps to research the
           contents of .svn/props directories).

           The DIRNAME must always be a simple directory name. Nested directories like foo/bar are NOT
           supported. You would need to specify --ignore-dir=foo and then no files from any foo directory are
           taken into account by ack-grep unless given explicitly on the command line.

       --ignore-file=FILTERTYPE:FILTERARGS
           Ignore files matching FILTERTYPE:FILTERARGS.  The filters are specified identically to file type
           filters as seen in "Defining your own types".

       -k, --known-types
           Limit selected files to those with types that ack-grep knows about.  This is equivalent to the
           default behavior found in ack-grep 1.

       --lines=NUM
           Only print line NUM of each file. Multiple lines can be given with multiple --lines options or as a
           comma separated list (--lines=3,5,7). --lines=4-7 also works. The lines are always output in
           ascending order, no matter the order given on the command line.

       -l, --files-with-matches
           Only print the filenames of matching files, instead of the matching text.

       -L, --files-without-matches
           Only print the filenames of files that do NOT match.

       --match PATTERN
           Specify the PATTERN explicitly. This is helpful if you don't want to put the regex as your first
           argument, e.g. when executing multiple searches over the same set of files.

               # search for foo and bar in given files
               ack-grep file1 t/file* --match foo
               ack-grep file1 t/file* --match bar

       -m=NUM, --max-count=NUM
           Stop reading a file after NUM matches.

       --man
           Print this manual page.

       -n, --no-recurse
           No descending into subdirectories.

       -o  Show only the part of each line matching PATTERN (turns off text highlighting)

       --output=expr
           Output the evaluation of expr for each line (turns off text highlighting) If PATTERN matches more
           than once then a line is output for each non-overlapping match.  For more information please see the
           section "Examples of --output".

       --pager=program, --nopager
           --pager directs ack-grep's output through program.  This can also be specified via the "ACK_PAGER"
           and "ACK_PAGER_COLOR" environment variables.

           Using --pager does not suppress grouping and coloring like piping output on the command-line does.

           --nopager cancels any setting in ~/.ackrc, "ACK_PAGER" or "ACK_PAGER_COLOR".  No output will be sent
           through a pager.

       --passthru
           Prints all lines, whether or not they match the expression.  Highlighting will still work, though, so
           it can be used to highlight matches while still seeing the entire file, as in:

               # Watch a log file, and highlight a certain IP address
               $ tail -f ~/access.log | ack-grep --passthru 123.45.67.89

       --print0
           Only works in conjunction with -f, -g, -l or -c (filename output). The filenames are output separated
           with a null byte instead of the usual newline. This is helpful when dealing with filenames that
           contain whitespace, e.g.

               # remove all files of type html
               ack-grep -f --html --print0 | xargs -0 rm -f

       -Q, --literal
           Quote all metacharacters in PATTERN, it is treated as a literal.

       -r, -R, --recurse
           Recurse into sub-directories. This is the default and just here for compatibility with grep. You can
           also use it for turning --no-recurse off.

       -s  Suppress error messages about nonexistent or unreadable files.  This is taken from fgrep.

       --[no]smart-case, --no-smart-case
           Ignore case in the search strings if PATTERN contains no uppercase characters. This is similar to
           "smartcase" in vim. This option is off by default, and ignored if "-i" is specified.

           -i always overrides this option.

       --sort-files
           Sorts the found files lexicographically.  Use this if you want your file listings to be deterministic
           between runs of ack-grep.

       --show-types
           Outputs the filetypes that ack-grep associates with each file.

           Works with -f and -g options.

       --type=[no]TYPE
           Specify the types of files to include or exclude from a search.  TYPE is a filetype, like perl or
           xml.  --type=perl can also be specified as --perl, and --type=noperl can be done as --noperl.

           If a file is of both type "foo" and "bar", specifying --foo and --nobar will exclude the file,
           because an exclusion takes precedence over an inclusion.

           Type specifications can be repeated and are ORed together.

           See ack-grep --help=types for a list of valid types.

       --type-add TYPE:FILTER:FILTERARGS
           Files with the given FILTERARGS applied to the given FILTER are recognized as being of (the existing)
           type TYPE.  See also "Defining your own types".

       --type-set TYPE:FILTER:FILTERARGS
           Files with the given FILTERARGS applied to the given FILTER are recognized as being of type TYPE.
           This replaces an existing definition for type TYPE.  See also "Defining your own types".

       --type-del TYPE
           The filters associated with TYPE are removed from Ack, and are no longer considered for searches.

       -v, --invert-match
           Invert match: select non-matching lines

       --version
           Display version and copyright information.

       -w, --word-regexp
           Force PATTERN to match only whole words.  The PATTERN is wrapped with "\b" metacharacters.

       -x  An abbreviation for --files-from=-; the list of files to search are read from standard input, with
           one line per file.

       -1  Stops after reporting first match of any kind.  This is different from --max-count=1 or -m1, where
           only one match per file is shown.  Also, -1 works with -f and -g, where -m does not.

       --thpppt
           Display the all-important Bill The Cat logo.  Note that the exact spelling of --thpppppt is not
           important.  It's checked against a regular expression.

       --bar
           Check with the admiral for traps.

       --cathy
           Chocolate, Chocolate, Chocolate!

THE .ackrc FILE

       The .ackrc file contains command-line options that are prepended to the command line before processing.
       Multiple options may live on multiple lines.  Lines beginning with a # are ignored.  A .ackrc might look
       like this:

           # Always sort the files
           --sort-files

           # Always color, even if piping to a another program
           --color

           # Use "less -r" as my pager
           --pager=less -r

       Note that arguments with spaces in them do not need to be quoted, as they are not interpreted by the
       shell. Basically, each line in the .ackrc file is interpreted as one element of @ARGV.

       ack-grep looks in several locations for .ackrc files; the searching process is detailed in "ACKRC
       LOCATION SEMANTICS".  These files are not considered if --noenv is specified on the command line.

Defining your own types

       ack-grep allows you to define your own types in addition to the predefined types. This is done with
       command line options that are best put into an .ackrc file - then you do not have to define your types
       over and over again. In the following examples the options will always be shown on one command line so
       that they can be easily copy & pasted.

       ack-grep --perl foo searches for foo in all perl files. ack-grep --help=types tells you, that perl files
       are files ending in .pl, .pm, .pod or .t. So what if you would like to include .xs files as well when
       searching for --perl files? ack-grep --type-add perl:ext:xs --perl foo does this for you. --type-add
       appends additional extensions to an existing type.

       If you want to define a new type, or completely redefine an existing type, then use --type-set. ack-grep
       --type-set eiffel:ext:e,eiffel defines the type eiffel to include files with the extensions .e or
       .eiffel. So to search for all eiffel files containing the word Bertrand use ack-grep --type-set
       eiffel:ext:e,eiffel --eiffel Bertrand.  As usual, you can also write --type=eiffel instead of --eiffel.
       Negation also works, so --noeiffel excludes all eiffel files from a search. Redefining also works: ack-
       grep --type-set cc:ext:c,h and .xs files no longer belong to the type cc.

       When defining your own types in the .ackrc file you have to use the following:

         --type-set=eiffel:ext:e,eiffel

       or writing on separate lines

         --type-set
         eiffel:ext:e,eiffel

       The following does NOT work in the .ackrc file:

         --type-set eiffel:ext:e,eiffel

       In order to see all currently defined types, use --help-types, e.g.  ack-grep --type-set backup:ext:bak
       --type-add perl:ext:perl --help-types

       In addition to filtering based on extension (like ack-grep 1.x allowed), ack-grep 2 offers additional
       filter types.  The generic syntax is --type-set TYPE:FILTER:FILTERARGS; FILTERARGS depends on the value
       of FILTER.

       is:FILENAME
           is filters match the target filename exactly.  It takes exactly one argument, which is the name of
           the file to match.

           Example:

               --type-set make:is:Makefile

       ext:EXTENSION[,EXTENSION2[,...]]
           ext filters match the extension of the target file against a list of extensions.  No leading dot is
           needed for the extensions.

           Example:

               --type-set perl:ext:pl,pm,t

       match:PATTERN
           match filters match the target filename against a regular expression.  The regular expression is made
           case insensitive for the search.

           Example:

               --type-set make:match:/(gnu)?makefile/

       firstlinematch:PATTERN
           firstlinematch matches the first line of the target file against a regular expression.  Like match,
           the regular expression is made case insensitive.

           Example:

               --type-add perl:firstlinematch:/perl/

       More filter types may be made available in the future.

ENVIRONMENT VARIABLES

       For commonly-used ack-grep options, environment variables can make life much easier.  These variables are
       ignored if --noenv is specified on the command line.

       ACKRC
           Specifies the location of the user's .ackrc file.  If this file doesn't exist, ack-grep looks in the
           default location.

       ACK_OPTIONS
           This variable specifies default options to be placed in front of any explicit options on the command
           line.

       ACK_COLOR_FILENAME
           Specifies the color of the filename when it's printed in --group mode.  By default, it's "bold
           green".

           The recognized attributes are clear, reset, dark, bold, underline, underscore, blink, reverse,
           concealed black, red, green, yellow, blue, magenta, on_black, on_red, on_green, on_yellow, on_blue,
           on_magenta, on_cyan, and on_white.  Case is not significant.  Underline and underscore are
           equivalent, as are clear and reset.  The color alone sets the foreground color, and on_color sets the
           background color.

           This option can also be set with --color-filename.

       ACK_COLOR_MATCH
           Specifies the color of the matching text when printed in --color mode.  By default, it's "black
           on_yellow".

           This option can also be set with --color-match.

           See ACK_COLOR_FILENAME for the color specifications.

       ACK_COLOR_LINENO
           Specifies the color of the line number when printed in --color mode.  By default, it's "bold yellow".

           This option can also be set with --color-lineno.

           See ACK_COLOR_FILENAME for the color specifications.

       ACK_PAGER
           Specifies a pager program, such as "more", "less" or "most", to which ack-grep will send its output.

           Using "ACK_PAGER" does not suppress grouping and coloring like piping output on the command-line
           does, except that on Windows ack-grep will assume that "ACK_PAGER" does not support color.

           "ACK_PAGER_COLOR" overrides "ACK_PAGER" if both are specified.

       ACK_PAGER_COLOR
           Specifies a pager program that understands ANSI color sequences.  Using "ACK_PAGER_COLOR" does not
           suppress grouping and coloring like piping output on the command-line does.

           If you are not on Windows, you never need to use "ACK_PAGER_COLOR".

ACK & OTHER TOOLS

   Vim integration
       ack-grep integrates easily with the Vim text editor. Set this in your .vimrc to use ack-grep instead of
       grep:

           set grepprg=ack-grep\ -k

       That example uses "-k" to search through only files of the types ack-grep knows about, but you may use
       other default flags. Now you can search with ack-grep and easily step through the results in Vim:

         :grep Dumper perllib

       Miles Sterrett has written a Vim plugin for ack-grep which allows you to use ":Ack" instead of ":grep",
       as well as several other advanced features.

       <https://github.com/mileszs/ack.vim>

   Emacs integration
       Phil Jackson put together an ack.el extension that "provides a simple compilation mode ... has the
       ability to guess what files you want to search for based on the major-mode."

       <http://www.shellarchive.co.uk/content/emacs.html>

   TextMate integration
       Pedro Melo is a TextMate user who writes "I spend my day mostly inside TextMate, and the built-in find-
       in-project sucks with large projects.  So I hacked a TextMate command that was using find + grep to use
       ack-grep.  The result is the Search in Project with ack-grep, and you can find it here:
       <http://www.simplicidade.org/notes/archives/2008/03/search_in_proje.html>"

   Shell and Return Code
       For greater compatibility with grep, ack-grep in normal use returns shell return or exit code of 0 only
       if something is found and 1 if no match is found.

       (Shell exit code 1 is "$?=256" in perl with "system" or backticks.)

       The grep code 2 for errors is not used.

       If "-f" or "-g" are specified, then 0 is returned if at least one file is found.  If no files are found,
       then 1 is returned.

DEBUGGING ACK-GREP PROBLEMS

       If ack-grep gives you output you're not expecting, start with a few simple steps.

   Use --noenv
       Your environment variables and .ackrc may be doing things you're not expecting, or forgotten you
       specified.  Use --noenv to ignore your environment and .ackrc.

   Use -f to see what files have been selected
       Ack's -f was originally added as a debugging tool.  If ack-grep is not finding matches you think it
       should find, run ack-grep -f to see what files have been selected.  You can also add the "--show-types"
       options to show the type of each file selected.

   Use --dump
       This lists the ackrc files that are loaded and the options loaded from them.  So for example you can find
       a list of directories that do not get searched or where filetypes are defined.

TIPS

   Use the .ackrc file.
       The .ackrc is the place to put all your options you use most of the time but don't want to remember.  Put
       all your --type-add and --type-set definitions in it.  If you like --smart-case, set it there, too.  I
       also set --sort-files there.

   Use -f for working with big codesets
       Ack does more than search files.  "ack-grep -f --perl" will create a list of all the Perl files in a
       tree, ideal for sending into xargs.  For example:

           # Change all "this" to "that" in all Perl files in a tree.
           ack-grep -f --perl | xargs perl -p -i -e's/this/that/g'

       or if you prefer:

           perl -p -i -e's/this/that/g' $(ack-grep -f --perl)

   Use -Q when in doubt about metacharacters
       If you're searching for something with a regular expression metacharacter, most often a period in a
       filename or IP address, add the -Q to avoid false positives without all the backslashing.  See the
       following example for more...

   Use ack-grep to watch log files
       Here's one I used the other day to find trouble spots for a website visitor.  The user had a problem
       loading troublesome.gif, so I took the access log and scanned it with ack-grep twice.

           ack-grep -Q aa.bb.cc.dd /path/to/access.log | ack-grep -Q -B5 troublesome.gif

       The first ack-grep finds only the lines in the Apache log for the given IP.  The second finds the match
       on my troublesome GIF, and shows the previous five lines from the log in each case.

   Examples of --output
       Following variables are useful in the expansion string:

       $&  The whole string matched by PATTERN.

       $1, $2, ...
           The contents of the 1st, 2nd ... bracketed group in PATTERN.

       "$`"
           The string before the match.

       "$'"
           The string after the match.

       For more details and other variables see
       <http://perldoc.perl.org/perlvar.html#Variables-related-to-regular-expressions|perlvar>.

       This example shows how to add text around a particular pattern (in this case adding _ around word with
       "e")

           ack2.pl "\w*e\w*" quick.txt --output="$`_$&_$'"
           _The_ quick brown fox jumps over the lazy dog
           The quick brown fox jumps _over_ the lazy dog
           The quick brown fox jumps over _the_ lazy dog

       This shows how to pick out particular parts of a match using ( ) within regular expression.

         ack-grep '=head(\d+)\s+(.*)' --output=' $1 : $2'
         input file contains "=head1 NAME"
         output  "1 : NAME"

   Share your knowledge
       Join the ack-users mailing list.  Send me your tips and I may add them here.

FAQ

   Why isn't ack-grep finding a match in (some file)?
       Probably because it's of a type that ack-grep doesn't recognize.  ack-grep's searching behavior is driven
       by filetype.  If ack-grep doesn't know what kind of file it is, ack-grep ignores the file.

       Use the "-f" switch to see a list of files that ack-grep will search for you.  You can use the
       "--show-types" switch to show which type ack-grep thinks each file is.

   Wouldn't it be great if ack-grep did search & replace?
       No, ack-grep will always be read-only.  Perl has a perfectly good way to do search & replace in files,
       using the "-i", "-p" and "-n" switches.

       You can certainly use ack-grep to select your files to update.  For example, to change all "foo" to "bar"
       in all PHP files, you can do this from the Unix shell:

           $ perl -i -p -e's/foo/bar/g' $(ack-grep -f --php)

   Can I make ack-grep recognize .xyz files?
       Yes!  Please see "Defining your own types".  If you think that ack-grep should recognize a type by
       default, please see "ENHANCEMENTS".

   There's already a program/package called ack.
       Yes, I know.

   Why is it called ack-grep if it's called ack?
       The name of the program is "ack".  Some packagers have called it "ack-grep" when creating packages
       because there's already a package out there called "ack" that has nothing to do with this ack.

       I suggest you make a symlink named ack that points to ack-grep because one of the crucial benefits of ack
       is having a name that's so short and simple to type.

       To do that, run this with sudo or as root:

          ln -s /usr/bin/ack-grep /usr/bin/ack

       Alternatively, you could use a shell alias:

           # bash/zsh
           alias ack=ack-grep

           # csh
           alias ack ack-grep

   What does ack mean?
       Nothing.  I wanted a name that was easy to type and that you could pronounce as a single syllable.

   Can I do multi-line regexes?
       No, ack-grep does not support regexes that match multiple lines.  Doing so would require reading in the
       entire file at a time.

       If you want to see lines near your match, use the "--A", "--B" and "--C" switches for displaying context.

   Why is ack-grep telling me I have an invalid option when searching for "+foo"?
       ack-grep treats command line options beginning with "+" or "-" as options; if you would like to search
       for these, you may prefix your search term with "--" or use the "--match" option.  (However, don't forget
       that "+" is a regular expression metacharacter!)

   Why does "ack '.{40000,}'" fail?  Isn't that a valid regex?
       The Perl language limits the repetition quanitifier to 32K.  You can search for ".{32767}" but not
       ".{32768}".

ACKRC LOCATION SEMANTICS

       Ack can load its configuration from many sources.  This list specifies the sources Ack looks for
       configuration; each one that is found is loaded in the order specified here, and each one overrides
       options set in any of the sources preceding it.  (For example, if I set --sort-files in my user ackrc,
       and --nosort-files on the command line, the command line takes precedence)

       •   Defaults are loaded from App::Ack::ConfigDefaults.  This can be omitted using
           "--ignore-ack-defaults".

       •   Global ackrc

           Options are then loaded from the global ackrc.  This is located at "/etc/ackrc" on Unix-like systems,
           and "C:\Documents and Settings\All Users\Application Data\ackrc" on Windows.  This can be omitted
           using "--noenv".

       •   User ackrc

           Options are then loaded from the user's ackrc.  This is located at "$HOME/.ackrc" on Unix-like
           systems, and "C:\Documents and Settings\$USER\Application Data\ackrc".  If a different ackrc is
           desired, it may be overridden with the $ACKRC environment variable.  This can be omitted using
           "--noenv".

       •   Project ackrc

           Options are then loaded from the project ackrc.  The project ackrc is the first ackrc file with the
           name ".ackrc" or "_ackrc", first searching in the current directory, then the parent directory, then
           the grandparent directory, etc.  This can be omitted using "--noenv".

       •   --ackrc

           The "--ackrc" option may be included on the command line to specify an ackrc file that can override
           all others.  It is consulted even if "--noenv" is present.

       •   ACK_OPTIONS

           Options are then loaded from the environment variable "ACK_OPTIONS".  This can be omitted using
           "--noenv".

       •   Command line

           Options are then loaded from the command line.

DIFFERENCES BETWEEN ACK 1.X AND ACK 2.X

       A lot of changes were made for ack-grep 2; here is a list of them.

   GENERAL CHANGES
       •   When no selectors are specified, ack-grep 1.x only searches through files that it can map to a file
           type.  ack-grep 2.x, by contrast, will search through every regular, non-binary file that is not
           explicitly ignored via --ignore-file or --ignore-dir.  This is similar to the behavior of the
           -a/--all option in ack-grep 1.x.

       •   A more flexible filter system has been added, so that more powerful file types may be created by the
           user.  For details, please consult "Defining your own types".

       •   ack-grep now loads multiple ackrc files; see "ACKRC LOCATION SEMANTICS" for details.

       •   ack-grep's default filter definitions aren't special; you may tell ack-grep to completely disregard
           them if you don't like them.

   REMOVED OPTIONS
       •   Because of the change in default search behavior, the -a/--all and -u/--unrestricted options have
           been removed.  In addition, the -k/--known-types option was added to cause ack-grep to behave with
           the default search behavior of ack-grep 1.x.

       •   The -G option has been removed.  Two regular expressions on the command line was considered too
           confusing; to simulate -G's functionality, you may use the new -x option to pipe filenames from one
           invocation of ack-grep into another.

       •   The --binary option has been removed.

       •   The --skipped option has been removed.

       •   The --text option has been removed.

       •   The --invert-file-match option has been removed.  Instead, you may use -v with -g.

   CHANGED OPTIONS
       •   The options that modify the regular expression's behavior (-i, -w, -Q, and -v) may now be used with
           -g.

   ADDED OPTIONS--files-from was added so that a user may submit a list of filenames as a list of files to search.

       •   -x was added to tell ack-grep to accept a list of filenames via standard input; this list is the list
           of filenames that will be used for the search.

       •   -s was added to tell ack-grep to suppress error messages about non-existent or unreadable files.

       •   --ignore-directory and --noignore-directory were added as aliases for --ignore-dir and --noignore-dir
           respectively.

       •   --ignore-file was added so that users may specify patterns of files to ignore (ex. /.*~$/).

       •   --dump was added to allow users to easily find out which options are set where.

       •   --create-ackrc was added so that users may create custom ackrc files based on the default settings
           loaded by ack-grep, and so that users may easily view those defaults.

       •   --type-del was added to selectively remove file type definitions.

       •   --ignore-ack-defaults was added so that users may ignore ack-grep's default options in favor of their
           own.

       •   --bar was added so ack-grep users may consult Admiral Ackbar.

AUTHOR

       Andy Lester, "<andy at petdance.com>"

BUGS

       Please report any bugs or feature requests to the issues list at Github:
       <https://github.com/petdance/ack2/issues>

ENHANCEMENTS

       All enhancement requests MUST first be posted to the ack-users mailing list at
       <http://groups.google.com/group/ack-users>.  I will not consider a request without it first getting seen
       by other ack-grep users.  This includes requests for new filetypes.

       There is a list of enhancements I want to make to ack-grep in the ack issues list at Github:
       <https://github.com/petdance/ack2/issues>

       Patches are always welcome, but patches with tests get the most attention.

SUPPORT

       Support for and information about ack-grep can be found at:

       •   The ack homepage

           <http://beyondgrep.com/>

       •   The ack-users mailing list

           <http://groups.google.com/group/ack-users>

       •   The ack issues list at Github

           <https://github.com/petdance/ack2/issues>

       •   AnnoCPAN: Annotated CPAN documentation

           <http://annocpan.org/dist/ack>

       •   CPAN Ratings

           <http://cpanratings.perl.org/d/ack>

       •   Search CPAN

           <http://search.cpan.org/dist/ack>

       •   Git source repository

           <https://github.com/petdance/ack2>

ACKNOWLEDGEMENTS

       How appropriate to have acknowledgements!

       Thanks to everyone who has contributed to ack-grep in any way, including Fraser Tweedale, Raal Gundan,
       Steffen Jaeckel, Stephan Hohe, Michael Beijen, Alexandr Ciornii, Christian Walde, Charles Lee, Joe
       McMahon, John Warwick, David Steinbrunner, Kara Martens, Volodymyr Medvid, Ron Savage, Konrad Borowski,
       Dale Sedivic, Michael McClimon, Andrew Black, Ralph Bodenner, Shaun Patterson, Ryan Olson, Shlomi Fish,
       Karen Etheridge, Olivier Mengue, Matthew Wild, Scott Kyle, Nick Hooey, Bo Borgerson, Mark Szymanski, Marq
       Schneider, Packy Anderson, JR Boyens, Dan Sully, Ryan Niebur, Kent Fredric, Mike Morearty, Ingmar
       Vanhassel, Eric Van Dewoestine, Sitaram Chamarty, Adam James, Richard Carlsson, Pedro Melo, AJ Schuster,
       Phil Jackson, Michael Schwern, Jan Dubois, Christopher J. Madsen, Matthew Wickline, David Dyck, Jason
       Porritt, Jjgod Jiang, Thomas Klausner, Uri Guttman, Peter Lewis, Kevin Riggle, Ori Avtalion, Torsten
       Blix, Nigel Metheringham, Gabor Szabo, Tod Hagan, Michael Hendricks, AEvar Arnfjoer` Bjarmason, Piers
       Cawley, Stephen Steneker, Elias Lutfallah, Mark Leighton Fisher, Matt Diephouse, Christian Jaeger, Bill
       Sully, Bill Ricker, David Golden, Nilson Santos F. Jr, Elliot Shank, Merijn Broeren, Uwe Voelker, Rick
       Scott, Ask Bjorn Hansen, Jerry Gay, Will Coleda, Mike O'Regan, Slaven ReziX, Mark Stosberg, David Alan
       Pisoni, Adriano Ferreira, James Keenan, Leland Johnson, Ricardo Signes, Pete Krawczyk and Rob Hoelz.

       Copyright 2005-2013 Andy Lester.

       This program is free software; you can redistribute it and/or modify it under the terms of the Artistic
       License v2.0.

       See http://www.perlfoundation.org/artistic_license_2_0 or the LICENSE.md file that comes with the ack
       distribution.