1ACK(1) User Contributed Perl Documentation ACK(1)
2
6 ack - grep-like text finder
7
9 ack [options] PATTERN [FILE...]
10 ack -f [options] [DIRECTORY...]
11
13 ack is designed as an alternative to grep for programmers.
14 ack searches the named input FILEs or DIRECTORYs for lines containing a
16 match to the given PATTERN. By default, ack prints the matching lines.
17 If no FILE or DIRECTORY is given, the current directory will be
18 searched.
19 PATTERN is a Perl regular expression. Perl regular expressions are
21 commonly found in other programming languages, but for the particulars
22 of their behavior, please consult perlreref
23 <https://perldoc.perl.org/perlreref.html>. If you don't know how to
24 use regular expression but are interested in learning, you may consult
25 perlretut <https://perldoc.perl.org/perlretut.html>. If you do not
26 need or want ack to use regular expressions, please see the
27 "-Q"/"--literal" option.
28 Ack can also list files that would be searched, without actually
30 searching them, to let you take advantage of ack's file-type filtering
31 capabilities.
32
34 If files are not specified for searching, either on the command line or
35 piped in with the "-x" option, ack delves into subdirectories selecting
36 files for searching.
37 ack is intelligent about the files it searches. It knows about certain
39 file types, based on both the extension on the file and, in some cases,
40 the contents of the file. These selections can be made with the --type
41 option.
42 With no file selection, ack searches through regular files that are not
44 explicitly excluded by --ignore-dir and --ignore-file options, either
45 present in ackrc files or on the command line.
46 The default options for ack ignore certain files and directories.
48 These include:
49 · Backup files: Files matching #*# or ending with ~.
51 · Coredumps: Files matching core.\d+
53 · Version control directories like .svn and .git.
55 Run ack with the "--dump" option to see what settings are set.
57 However, ack always searches the files given on the command line, no
59 matter what type. If you tell ack to search in a coredump, it will
60 search in a coredump.
61
63 ack descends through the directory tree of the starting directories
64 specified. If no directories are specified, the current working
65 directory is used. However, it will ignore the shadow directories used
66 by many version control systems, and the build directories used by the
67 Perl MakeMaker system. You may add or remove a directory from this
68 list with the --[no]ignore-dir option. The option may be repeated to
69 add/remove multiple directories from the ignore list.
70 For a complete list of directories that do not get searched, run "ack
72 --dump".
73
75 The "--range-start" and "--range-end" options let you specify ranges of
76 lines to search within each file.
77 Say you had the following file, called testfile:
79 # This function calls print on "foo".
81 sub foo {
82 print 'foo';
83 }
84 my $print = 1;
85 sub bar {
86 print 'bar';
87 }
88 my $task = 'print';
89 Calling "ack print" will give us five matches:
91 $ ack print testfile
93 # This function calls print on "foo".
94 print 'foo';
95 my $print = 1;
96 print 'bar';
97 my $task = 'print';
98 What if we only want to search for "print" within the subroutines? We
100 can specify ranges of lines that we want ack to search. The range
101 starts with any line that matches the pattern "^sub \w+", and stops
102 with any line that matches "^}".
103 $ ack --range-start='^sub \w+' --range-end='^}' print testfile
105 print 'foo';
106 print 'bar';
107 Note that ack searched two ranges of lines. The listing below shows
109 which lines were in a range and which were out of the range.
110 Out # This function calls print on "foo".
112 In sub foo {
113 In print 'foo';
114 In }
115 Out my $print = 1;
116 In sub bar {
117 In print 'bar';
118 In }
119 Out my $task = 'print';
120 You don't have to specify both "--range-start" and "--range-end". IF
122 "--range-start" is omitted, then the range runs from the first line in
123 the file unitl the first line that matches "--range-end". Similarly,
124 if "--range-end" is omitted, the range runs from the first line
125 matching "--range-start" to the end of the file.
126 For example, if you wanted to search all HTML files up until the first
128 instance of the "<body>", you could do
129 ack foo --range-end='<body>'
131 Or to search after Perl's `__DATA__` or `__END__` markers, you would do
133 ack pattern --range-end='^__(END|DATA)__'
135 It's possible for a range to start and stop on the same line. For
137 example
138 --range-start='<title>' --range-end='</title>'
140 would match this line as both the start and end of the range, making a
142 one-line range.
143 <title>Page title</title>
145 Note that the patterns in "--range-start" and "--range-end" are not
147 affected by options like "-i", "-w" and "-Q" that modify the behavior
148 of the main pattern being matched.
149 Again, ranges only affect where matches are looked for. Everything
151 else in ack works the same way. Using "-c" option with a range will
152 give a count of all the matches that appear within those ranges. The
153 "-l" shows those files that have a match within a range, and the "-L"
154 option shows files that do not have a match within a range.
155 The "-v" option for negating a match works inside the range, too. To
157 see lines that don't match "google" within the "<head>" section of your
158 HTML files, you could do:
159 ack google -v --html --range-start='<head' --range-end='</head>'
161 Specifying a range to search does not affect how matches are displayed.
163 The context for a match will still be the same, and
164 Using the context options work the same way, and will show context
166 lines for matches even if the context lines fall outside the range.
167 Similarly, "--passthru" will show all lines in the file, but only show
168 matches for lines within the range.
169
171 --ackrc
172 Specifies an ackrc file to load after all others; see "ACKRC
173 LOCATION SEMANTICS".
174 -A NUM, --after-context=NUM
176 Print NUM lines of trailing context after matching lines.
177 -B NUM, --before-context=NUM
179 Print NUM lines of leading context before matching lines.
180 --[no]break
182 Print a break between results from different files. On by default
183 when used interactively.
184 -C [NUM], --context[=NUM]
186 Print NUM lines (default 2) of context around matching lines. You
187 can specify zero lines of context to override another context
188 specified in an ackrc.
189 -c, --count
191 Suppress normal output; instead print a count of matching lines for
192 each input file. If -l is in effect, it will only show the number
193 of lines for each file that has lines matching. Without -l, some
194 line counts may be zeroes.
195 If combined with -h (--no-filename) ack outputs only one total
197 count.
198 --[no]color, --[no]colour
200 --color highlights the matching text. --nocolor suppresses the
201 color. This is on by default unless the output is redirected.
202 On Windows, this option is off by default unless the
204 Win32::Console::ANSI module is installed or the "ACK_PAGER_COLOR"
205 environment variable is used.
206 --color-filename=color
208 Sets the color to be used for filenames.
209 --color-match=color
211 Sets the color to be used for matches.
212 --color-colno=color
214 Sets the color to be used for column numbers.
215 --color-lineno=color
217 Sets the color to be used for line numbers.
218 --[no]column
220 Show the column number of the first match. This is helpful for
221 editors that can place your cursor at a given position.
222 --create-ackrc
224 Dumps the default ack options to standard output. This is useful
225 for when you want to customize the defaults.
226 --dump
228 Writes the list of options loaded and where they came from to
229 standard output. Handy for debugging.
230 --[no]env
232 --noenv disables all environment processing. No .ackrc is read and
233 all environment variables are ignored. By default, ack considers
234 .ackrc and settings in the environment.
235 --flush
237 --flush flushes output immediately. This is off by default unless
238 ack is running interactively (when output goes to a pipe or file).
239 -f Only print the files that would be searched, without actually doing
241 any searching. PATTERN must not be specified, or it will be taken
242 as a path to search.
243 --files-from=FILE
245 The list of files to be searched is specified in FILE. The list of
246 files are separated by newlines. If FILE is "-", the list is
247 loaded from standard input.
248 Note that the list of files is not filtered in any way. If you add
250 "--type=html" in addition to "--files-from", the "--type" will be
251 ignored.
252 --[no]filter
254 Forces ack to act as if it were receiving input via a pipe.
255 --[no]follow
257 Follow or don't follow symlinks, other than whatever starting files
258 or directories were specified on the command line.
259 This is off by default.
261 -g PATTERN
263 Print searchable files where the relative path + filename matches
264 PATTERN.
265 Note that
267 ack -g foo
269 is exactly the same as
271 ack -f | ack foo
273 This means that just as ack will not search, for example, .jpg
275 files, "-g" will not list .jpg files either. ack is not intended
276 to be a general-purpose file finder.
277 Note also that if you have "-i" in your .ackrc that the filenames
279 to be matched will be case-insensitive as well.
280 This option can be combined with --color to make it easier to spot
282 the match.
283 --[no]group
285 --group groups matches by file name. This is the default when used
286 interactively.
287 --nogroup prints one result per line, like grep. This is the
289 default when output is redirected.
290 -H, --with-filename
292 Print the filename for each match. This is the default unless
293 searching a single explicitly specified file.
294 -h, --no-filename
296 Suppress the prefixing of filenames on output when multiple files
297 are searched.
298 --[no]heading
300 Print a filename heading above each file's results. This is the
301 default when used interactively.
302 --help
304 Print a short help statement.
305 --help-types
307 Print all known types.
308 --help-colors
310 Print a chart of various color combinations.
311 --help-rgb-colors
313 Like --help-colors but with more precise RGB colors.
314 -i, --ignore-case
316 Ignore case distinctions in PATTERN. Overrides --smart-case and
317 -I.
318 -I, --no-ignore-case
320 Turns on case distinctions in PATTERN. Overrides --smart-case and
321 -i.
322 --ignore-ack-defaults
324 Tells ack to completely ignore the default definitions provided
325 with ack. This is useful in combination with --create-ackrc if you
326 really want to customize ack.
327 --[no]ignore-dir=DIRNAME, --[no]ignore-directory=DIRNAME
329 Ignore directory (as CVS, .svn, etc are ignored). May be used
330 multiple times to ignore multiple directories. For example, mason
331 users may wish to include --ignore-dir=data. The --noignore-dir
332 option allows users to search directories which would normally be
333 ignored (perhaps to research the contents of .svn/props
334 directories).
335 The DIRNAME must always be a simple directory name. Nested
337 directories like foo/bar are NOT supported. You would need to
338 specify --ignore-dir=foo and then no files from any foo directory
339 are taken into account by ack unless given explicitly on the
340 command line.
341 --ignore-file=FILTER:ARGS
343 Ignore files matching FILTER:ARGS. The filters are specified
344 identically to file type filters as seen in "Defining your own
345 types".
346 -k, --known-types
348 Limit selected files to those with types that ack knows about.
349 -l, --files-with-matches
351 Only print the filenames of matching files, instead of the matching
352 text.
353 -L, --files-without-matches
355 Only print the filenames of files that do NOT match.
356 --match PATTERN
358 Specify the PATTERN explicitly. This is helpful if you don't want
359 to put the regex as your first argument, e.g. when executing
360 multiple searches over the same set of files.
361 # search for foo and bar in given files
363 ack file1 t/file* --match foo
364 ack file1 t/file* --match bar
365 -m=NUM, --max-count=NUM
367 Print only NUM matches out of each file. If you want to stop ack
368 after printing the first match of any kind, use the -1 options.
369 --man
371 Print this manual page.
372 -n, --no-recurse
374 No descending into subdirectories.
375 -o Show only the part of each line matching PATTERN (turns off text
377 highlighting). This is exactly the same as "--output=$&".
378 --output=expr
380 Output the evaluation of expr for each line (turns off text
381 highlighting). If PATTERN matches more than once then a line is
382 output for each non-overlapping match.
383 expr may contain the strings "\n", "\r" and "\t", which will be
385 expanded to their corresponding characters line feed, carriage
386 return and tab, respectively.
387 expr may also contain the following Perl special variables:
389 $1 through $9
391 The subpattern from the corresponding set of capturing
392 parentheses. If your pattern is "(.+) and (.+)", and the
393 string is "this and that', then $1 is "this" and $2 is "that".
394 $_ The contents of the line in the file.
396 $. The number of the line in the file.
398 $&, "$`" and "$'"
400 $& is the the string matched by the pattern, "$`" is what
401 precedes the match, and "$'" is what follows it. If the
402 pattern is "gra(ph|nd)" and the string is "lexicographic", then
403 $& is "graph", "$`" is "lexico" and "$'" is "ic".
404 Use of these variables in your output will slow down the
406 pattern matching.
407 $+ The match made by the last parentheses that matched in the
409 pattern. For example, if your pattern is "Version:
410 (.+)|Revision: (.+)", then $+ will contain whichever set of
411 parentheses matched.
412 $f $f is available, in "--output" only, to insert the filename.
414 This is a stand-in for the discovered $filename usage in old
415 "ack2 --output", which is disallowed with "ack3" improved
416 security.
417 The intended usage is to provide the grep or compile-error
419 syntax needed for editor/IDE go-to-line integration, e.g.
420 "--output=$f:$.:$_" or "--output=$f\t$.\t$&"
421 --pager=program, --nopager
423 --pager directs ack's output through program. This can also be
424 specified via the "ACK_PAGER" and "ACK_PAGER_COLOR" environment
425 variables.
426 Using --pager does not suppress grouping and coloring like piping
428 output on the command-line does.
429 --nopager cancels any setting in ~/.ackrc, "ACK_PAGER" or
431 "ACK_PAGER_COLOR". No output will be sent through a pager.
432 --passthru
434 Prints all lines, whether or not they match the expression.
435 Highlighting will still work, though, so it can be used to
436 highlight matches while still seeing the entire file, as in:
437 # Watch a log file, and highlight a certain IP address.
439 $ tail -f ~/access.log | ack --passthru 123.45.67.89
440 --print0
442 Only works in conjunction with -f, -g, -l or -c, options that only
443 list filenames. The filenames are output separated with a null
444 byte instead of the usual newline. This is helpful when dealing
445 with filenames that contain whitespace, e.g.
446 # Remove all files of type HTML.
448 ack -f --html --print0 | xargs -0 rm -f
449 -p[N], --proximate[=N]
451 Groups together match lines that are within N lines of each other.
452 This is useful for visually picking out matches that appear close
453 to other matches.
454 For example, if you got these results without the "--proximate"
456 option,
457 15: First match
459 18: Second match
460 19: Third match
461 37: Fourth match
462 they would look like this with "--proximate=1"
464 15: First match
466 18: Second match
468 19: Third match
469 37: Fourth match
471 and this with "--proximate=3".
473 15: First match
475 18: Second match
476 19: Third match
477 37: Fourth match
479 If N is omitted, N is set to 1.
481 -P Negates the effect of the --proximate option. Shortcut for
483 --proximate=0.
484 -Q, --literal
486 Quote all metacharacters in PATTERN, it is treated as a literal.
487 -r, -R, --recurse
489 Recurse into sub-directories. This is the default and just here for
490 compatibility with grep. You can also use it for turning
491 --no-recurse off.
492 --range-start=PATTERN, --range-end=PATTERN
494 Specifies patterns that mark the start and end of a range. See
495 "MATCHING IN A RANGE OF LINES" for details.
496 -s Suppress error messages about nonexistent or unreadable files.
498 This is taken from fgrep.
499 -S, --[no]smart-case, --no-smart-case
501 Ignore case in the search strings if PATTERN contains no uppercase
502 characters. This is similar to "smartcase" in the vim text editor.
503 The options overrides -i and -I.
504 -S is a synonym for --smart-case.
506 -i always overrides this option.
508 --sort-files
510 Sorts the found files lexicographically. Use this if you want your
511 file listings to be deterministic between runs of ack.
512 --show-types
514 Outputs the filetypes that ack associates with each file.
515 Works with -f and -g options.
517 -t TYPE, --type=TYPE, --TYPE
519 Specify the types of files to include in the search. TYPE is a
520 filetype, like perl or xml. --type=perl can also be specified as
521 --perl, although this is deprecated.
522 Type inclusions can be repeated and are ORed together.
524 See ack --help-types for a list of valid types.
526 -T TYPE, --type=noTYPE, --noTYPE
528 Specifies the type of files to exclude from the search.
529 --type=noperl can be done as --noperl, although this is deprecated.
530 If a file is of both type "foo" and "bar", specifying both
532 --type=foo and --type=nobar will exclude the file, because an
533 exclusion takes precedence over an inclusion.
534 --type-add TYPE:FILTER:ARGS
536 Files with the given ARGS applied to the given FILTER are
537 recognized as being of (the existing) type TYPE. See also
538 "Defining your own types".
539 --type-set TYPE:FILTER:ARGS
541 Files with the given ARGS applied to the given FILTER are
542 recognized as being of type TYPE. This replaces an existing
543 definition for type TYPE. See also "Defining your own types".
544 --type-del TYPE
546 The filters associated with TYPE are removed from Ack, and are no
547 longer considered for searches.
548 --[no]underline
550 Turns on underlining of matches, where "underlining" is printing a
551 line of carets under the match.
552 $ ack -u foo
554 peanuts.txt
555 17: Come kick the football you fool
556 ^^^ ^^^
557 623: Price per square foot
558 ^^^
559 This is useful if you're dumping the results of an ack run into a
561 text file or printer that doesn't support ANSI color codes.
562 The setting of underline does not affect highlighting of matches.
564 -v, --invert-match
566 Invert match: select non-matching lines.
567 --version
569 Display version and copyright information.
570 -w, --word-regexp
572 Force PATTERN to match only whole words.
573 -x An abbreviation for --files-from=-. The list of files to search are
575 read from standard input, with one line per file.
576 Note that the list of files is not filtered in any way. If you add
578 "--type=html" in addition to "-x", the "--type" will be ignored.
579 -1 Stops after reporting first match of any kind. This is different
581 from --max-count=1 or -m1, where only one match per file is shown.
582 Also, -1 works with -f and -g, where -m does not.
583 --thpppt
585 Display the all-important Bill The Cat logo. Note that the exact
586 spelling of --thpppppt is not important. It's checked against a
587 regular expression.
588 --bar
590 Check with the admiral for traps.
591 --cathy
593 Chocolate, Chocolate, Chocolate!
594
596 The .ackrc file contains command-line options that are prepended to the
597 command line before processing. Multiple options may live on multiple
598 lines. Lines beginning with a # are ignored. A .ackrc might look like
599 this:
600 # Always sort the files
602 --sort-files
603 # Always color, even if piping to another program
605 --color
606 # Use "less -r" as my pager
608 --pager=less -r
609 Note that arguments with spaces in them do not need to be quoted, as
611 they are not interpreted by the shell. Basically, each line in the
612 .ackrc file is interpreted as one element of @ARGV.
613 ack looks in several locations for .ackrc files; the searching process
615 is detailed in "ACKRC LOCATION SEMANTICS". These files are not
616 considered if --noenv is specified on the command line.
617
619 ack allows you to define your own types in addition to the predefined
620 types. This is done with command line options that are best put into an
621 .ackrc file - then you do not have to define your types over and over
622 again. In the following examples the options will always be shown on
623 one command line so that they can be easily copy & pasted.
624 File types can be specified both with the the --type=xxx option, or the
626 file type as an option itself. For example, if you create a filetype
627 of "cobol", you can specify --type=cobol or simply --cobol. File types
628 must be at least two characters long. This is why the C language is
629 --cc and the R language is --rr.
630 ack --perl foo searches for foo in all perl files. ack --help-types
632 tells you, that perl files are files ending in .pl, .pm, .pod or .t. So
633 what if you would like to include .xs files as well when searching for
634 --perl files? ack --type-add perl:ext:xs --perl foo does this for you.
635 --type-add appends additional extensions to an existing type.
636 If you want to define a new type, or completely redefine an existing
638 type, then use --type-set. ack --type-set eiffel:ext:e,eiffel defines
639 the type eiffel to include files with the extensions .e or .eiffel. So
640 to search for all eiffel files containing the word Bertrand use ack
641 --type-set eiffel:ext:e,eiffel --eiffel Bertrand. As usual, you can
642 also write --type=eiffel instead of --eiffel. Negation also works, so
643 --noeiffel excludes all eiffel files from a search. Redefining also
644 works: ack --type-set cc:ext:c,h and .xs files no longer belong to the
645 type cc.
646 When defining your own types in the .ackrc file you have to use the
648 following:
649 --type-set=eiffel:ext:e,eiffel
651 or writing on separate lines
653 --type-set
655 eiffel:ext:e,eiffel
656 The following does NOT work in the .ackrc file:
658 --type-set eiffel:ext:e,eiffel
660 In order to see all currently defined types, use --help-types, e.g.
662 ack --type-set backup:ext:bak --type-add perl:ext:perl --help-types
663 In addition to filtering based on extension, ack offers additional
665 filter types. The generic syntax is --type-set TYPE:FILTER:ARGS; ARGS
666 depends on the value of FILTER.
667 is:FILENAME
669 is filters match the target filename exactly. It takes exactly one
670 argument, which is the name of the file to match.
671 Example:
673 --type-set make:is:Makefile
675 ext:EXTENSION[,EXTENSION2[,...]]
677 ext filters match the extension of the target file against a list
678 of extensions. No leading dot is needed for the extensions.
679 Example:
681 --type-set perl:ext:pl,pm,t
683 match:PATTERN
685 match filters match the target filename against a regular
686 expression. The regular expression is made case-insensitive for
687 the search.
688 Example:
690 --type-set make:match:/(gnu)?makefile/
692 firstlinematch:PATTERN
694 firstlinematch matches the first line of the target file against a
695 regular expression. Like match, the regular expression is made
696 case insensitive.
697 Example:
699 --type-add perl:firstlinematch:/perl/
701
703 ack allows customization of the colors it uses when presenting matches
704 onscreen. It uses the colors available in Perl's Term::ANSIColor
705 module, which provides the following listed values. Note that case does
706 not matter when using these values.
707 There are four different colors ack uses:
709 Aspect Option Env. variable Default
711 -------- ----------------- ------------------ ---------------
712 filename --color-filename ACK_COLOR_FILENAME black on_yellow
713 match --color-match ACK_COLOR_MATCH bold green
714 line no. --color-lineno ACK COLOR_LINENO bold yellow
715 column no. --color-colno ACK COLOR_COLNO bold yellow
716 The column number column is only used if the column number is shown
718 because of the --column option.
719 Colors may be specified by command-line option, such as "ack
721 --color-filename='red on_white'", or by setting an environment
722 variable, such as "ACK_COLOR_FILENAME='red on_white'". Options for
723 colors can be set in your ACKRC file (See "THE .ackrc FILE").
724 ack can understand the following colors for the foreground:
726 black red green yellow blue magenta cyan white
728 The optional background color is specified by prepending "on_" to one
730 of the foreground colors:
731 on_black on_red on_green on_yellow on_blue on_magenta on_cyan on_white
733 Each of the foreground colors can be modified with the following
735 attributes, which may or may not be supported by your terminal:
736 bold faint italic underline blink reverse concealed
738 Any combinations of modifiers can be added to the foreground color. If
740 your terminal supports it, and you enjoy visual punishment, you can
741 specify:
742 ack --color-filename="blink italic underline bold red on_yellow"
744 For charts of the colors and what they look like, run "ack
746 --help-colors" and "ack --help-rgb-colors".
747 If the eight standard colors, in their bold, faint and unmodified
749 states, aren't enough for you to choose from, you can also specify
750 colors by their RGB values. They are specified as "rgbXYZ" where X, Y,
751 and Z are values between 0 and 5 giving the intensity of red, green and
752 blue, respectively. Therefore, "rgb500" is pure red, "rgb505" is
753 purple, and so on.
754 Background colors can be specified with the "on_" prefix prepended on
756 an RGB color, so that "on_rgb505" would be a purple background.
757 The modifier attributes of blink, italic, underscore and so on may or
759 may not work on the RGB colors.
760 For a chart of the 216 possible RGB colors, run "ack
762 --help-rgb-colors".
763
765 For commonly-used ack options, environment variables can make life much
766 easier. These variables are ignored if --noenv is specified on the
767 command line.
768 ACKRC
770 Specifies the location of the user's .ackrc file. If this file
771 doesn't exist, ack looks in the default location.
772 ACK_COLOR_COLNO
774 Color specification for the column number in ack's output. By
775 default, the column number is not shown. You have to enable it
776 with the --column option. See the section "ack Colors" above.
777 ACK_COLOR_FILENAME
779 Color specification for the filename in ack's output. See the
780 section "ack Colors" above.
781 ACK_COLOR_LINENO
783 Color specification for the line number in ack's output. See the
784 section "ack Colors" above.
785 ACK_COLOR_MATCH
787 Color specification for the matched text in ack's output. See the
788 section "ack Colors" above.
789 ACK_PAGER
791 Specifies a pager program, such as "more", "less" or "most", to
792 which ack will send its output.
793 Using "ACK_PAGER" does not suppress grouping and coloring like
795 piping output on the command-line does, except that on Windows ack
796 will assume that "ACK_PAGER" does not support color.
797 "ACK_PAGER_COLOR" overrides "ACK_PAGER" if both are specified.
799 ACK_PAGER_COLOR
801 Specifies a pager program that understands ANSI color sequences.
802 Using "ACK_PAGER_COLOR" does not suppress grouping and coloring
803 like piping output on the command-line does.
804 If you are not on Windows, you never need to use "ACK_PAGER_COLOR".
806
808 Simple vim integration
809 ack integrates easily with the Vim text editor. Set this in your .vimrc
810 to use ack instead of grep:
811 set grepprg=ack\ -k
813 That example uses "-k" to search through only files of the types ack
815 knows about, but you may use other default flags. Now you can search
816 with ack and easily step through the results in Vim:
817 :grep Dumper perllib
819 Editor integration
821 Many users have integrated ack into their preferred text editors. For
822 details and links, see <https://beyondgrep.com/more-tools/>.
823 Shell and Return Code
825 For greater compatibility with grep, ack in normal use returns shell
826 return or exit code of 0 only if something is found and 1 if no match
827 is found.
828 (Shell exit code 1 is "$?=256" in perl with "system" or backticks.)
830 The grep code 2 for errors is not used.
832 If "-f" or "-g" are specified, then 0 is returned if at least one file
834 is found. If no files are found, then 1 is returned.
835
837 If ack gives you output you're not expecting, start with a few simple
838 steps.
839 Try it with --noenv
841 Your environment variables and .ackrc may be doing things you're not
842 expecting, or forgotten you specified. Use --noenv to ignore your
843 environment and .ackrc.
844 Use -f to see what files have been selected for searching
846 Ack's -f was originally added as a debugging tool. If ack is not
847 finding matches you think it should find, run ack -f to see what files
848 have been selected. You can also add the "--show-types" options to
849 show the type of each file selected.
850 Use --dump
852 This lists the ackrc files that are loaded and the options loaded from
853 them. You may be loading an .ackrc file that you didn't know you were
854 loading.
855
857 Ack can load its configuration from many sources. The following list
858 specifies the sources Ack looks for configuration files; each one that
859 is found is loaded in the order specified here, and each one overrides
860 options set in any of the sources preceding it. (For example, if I set
861 --sort-files in my user ackrc, and --nosort-files on the command line,
862 the command line takes precedence)
863 · Defaults are loaded from App::Ack::ConfigDefaults. This can be
865 omitted using "--ignore-ack-defaults".
866 · Global ackrc
868 Options are then loaded from the global ackrc. This is located at
870 "/etc/ackrc" on Unix-like systems.
871 Under Windows XP and earlier, the global ackrc is at "C:\Documents
873 and Settings\All Users\Application Data\ackrc"
874 Under Windows Vista/7, the global ackrc is at
876 "C:\ProgramData\ackrc"
877 The "--noenv" option prevents all ackrc files from being loaded.
879 · User ackrc
881 Options are then loaded from the user's ackrc. This is located at
883 "$HOME/.ackrc" on Unix-like systems.
884 Under Windows XP and earlier, the user's ackrc is at "C:\Documents
886 and Settings\$USER\Application Data\ackrc".
887 Under Windows Vista/7, the user's ackrc is at
889 "C:\Users\$USER\AppData\Roaming\ackrc".
890 If you want to load a different user-level ackrc, it may be
892 specified with the $ACKRC environment variable.
893 The "--noenv" option prevents all ackrc files from being loaded.
895 · Project ackrc
897 Options are then loaded from the project ackrc. The project ackrc
899 is the first ackrc file with the name ".ackrc" or "_ackrc", first
900 searching in the current directory, then the parent directory, then
901 the grandparent directory, etc. This can be omitted using
902 "--noenv".
903 · --ackrc
905 The "--ackrc" option may be included on the command line to specify
907 an ackrc file that can override all others. It is consulted even
908 if "--noenv" is present.
909 · Command line
911 Options are then loaded from the command line.
913
915 ack is based at GitHub at <https://github.com/beyondgrep/ack3>
916 Please report any bugs or feature requests to the issues list at
918 Github: <https://github.com/beyondgrep/ack3/issues>.
919 Please include the operating system that you're using; the output of
921 the command "ack --version"; and any customizations in your .ackrc you
922 may have.
923 To suggest enhancements, please submit an issue at
925 <https://github.com/beyondgrep/ack3/issues>. Also read the
926 DEVELOPERS.md file in the ack code repository.
927 Also, feel free to discuss your issues on the ack mailing list at
929 <https://groups.google.com/group/ack-users>.
930
932 Support for and information about ack can be found at:
933 · The ack homepage
935 <https://beyondgrep.com/>
937 · Source repository
939 <https://github.com/beyondgrep/ack3>
941 · The ack issues list at Github
943 <https://github.com/beyondgrep/ack3/issues>
945 · The ack announcements mailing list
947 <https://groups.google.com/group/ack-announcement>
949 · The ack users' mailing list
951 <https://groups.google.com/group/ack-users>
953 · The ack development mailing list
955 <https://groups.google.com/group/ack-users>
957
959 There are ack mailing lists and a Slack channel for ack. See
960 <https://beyondgrep.com/community/> for details.
961
963 This is the Frequently Asked Questions list for ack.
964 Can I stop using grep now?
966 Many people find ack to be better than grep as an everyday tool 99% of
967 the time, but don't throw grep away, because there are times you'll
968 still need it. For example, you might be looking through huge log
969 files and not using regular expressions. In that case, grep will
970 probably perform better.
971 Why isn't ack finding a match in (some file)?
973 First, take a look and see if ack is even looking at the file. ack is
974 intelligent in what files it will search and which ones it won't, but
975 sometimes that can be surprising.
976 Use the "-f" switch, with no regex, to see a list of files that ack
978 will search for you. If your file doesn't show up in the list of files
979 that "ack -f" shows, then ack never looks in it.
980 Wouldn't it be great if ack did search & replace?
982 No, ack will always be read-only. Perl has a perfectly good way to do
983 search & replace in files, using the "-i", "-p" and "-n" switches.
984 You can certainly use ack to select your files to update. For example,
986 to change all "foo" to "bar" in all PHP files, you can do this from the
987 Unix shell:
988 $ perl -i -p -e's/foo/bar/g' $(ack -f --php)
990 Can I make ack recognize .xyz files?
992 Yes! Please see "Defining your own types" in the ack manual.
993 Will you make ack recognize .xyz files by default?
995 We might, depending on how widely-used the file format is.
996 Submit an issue at in the GitHub issue queue at
998 <https://github.com/beyondgrep/ack3/issues>. Explain what the file
999 format is, where we can find out more about it, and what you have been
1000 using in your .ackrc to support it.
1001 Please do not bother creating a pull request. The code for filetypes
1003 is trivial compared to the rest of the process we go through.
1004 Why is it called ack if it's called ack-grep?
1006 The name of the program is "ack". Some packagers have called it "ack-
1007 grep" when creating packages because there's already a package out
1008 there called "ack" that has nothing to do with this ack.
1009 I suggest you make a symlink named ack that points to ack-grep because
1011 one of the crucial benefits of ack is having a name that's so short and
1012 simple to type.
1013 To do that, run this with sudo or as root:
1015 ln -s /usr/bin/ack-grep /usr/bin/ack
1017 Alternatively, you could use a shell alias:
1019 # bash/zsh
1021 alias ack=ack-grep
1022 # csh
1024 alias ack ack-grep
1025 What does ack mean?
1027 Nothing. I wanted a name that was easy to type and that you could
1028 pronounce as a single syllable.
1029 Can I do multi-line regexes?
1031 No, ack does not support regexes that match multiple lines. Doing so
1032 would require reading in the entire file at a time.
1033 If you want to see lines near your match, use the "--A", "--B" and
1035 "--C" switches for displaying context.
1036 Why is ack telling me I have an invalid option when searching for "+foo"?
1038 ack treats command line options beginning with "+" or "-" as options;
1039 if you would like to search for these, you may prefix your search term
1040 with "--" or use the "--match" option. (However, don't forget that "+"
1041 is a regular expression metacharacter!)
1042 Why does "ack '.{40000,}'" fail? Isn't that a valid regex?
1044 The Perl language limits the repetition quantifier to 32K. You can
1045 search for ".{32767}" but not ".{32768}".
1046 Ack does "X" and shouldn't, should it?
1048 We try to remain as close to grep's behavior as possible, so when in
1049 doubt, see what grep does! If there's a mismatch in functionality
1050 there, please submit an issue to GitHub, and/or bring it up on the ack-
1051 users mailing list.
1052
1054 How appropriate to have acknowledgements!
1055 Thanks to everyone who has contributed to ack in any way, including Dan
1057 Book, Tomasz Konojacki, Salomon Smeke, M. Scott Ford, Anders Eriksson,
1058 H.Merijn Brand, Duke Leto, Gerhard Poul, Ethan Mallove, Marek Kubica,
1059 Ray Donnelly, Nikolaj Schumacher, Ed Avis, Nick Morrott, Austin
1060 Chamberlin, Varadinsky, Sébastien Feugère, Jakub Wilk, Pete Houston,
1061 Stephen Thirlwall, Jonah Bishop, Chris Rebert, Denis Howe, Raúl Gundín,
1062 James McCoy, Daniel Perrett, Steven Lee, Jonathan Perret, Fraser
1063 Tweedale, Raál Gundán, Steffen Jaeckel, Stephan Hohe, Michael Beijen,
1064 Alexandr Ciornii, Christian Walde, Charles Lee, Joe McMahon, John
1065 Warwick, David Steinbrunner, Kara Martens, Volodymyr Medvid, Ron
1066 Savage, Konrad Borowski, Dale Sedivic, Michael McClimon, Andrew Black,
1067 Ralph Bodenner, Shaun Patterson, Ryan Olson, Shlomi Fish, Karen
1068 Etheridge, Olivier Mengue, Matthew Wild, Scott Kyle, Nick Hooey, Bo
1069 Borgerson, Mark Szymanski, Marq Schneider, Packy Anderson, JR Boyens,
1070 Dan Sully, Ryan Niebur, Kent Fredric, Mike Morearty, Ingmar Vanhassel,
1071 Eric Van Dewoestine, Sitaram Chamarty, Adam James, Richard Carlsson,
1072 Pedro Melo, AJ Schuster, Phil Jackson, Michael Schwern, Jan Dubois,
1073 Christopher J. Madsen, Matthew Wickline, David Dyck, Jason Porritt,
1074 Jjgod Jiang, Thomas Klausner, Uri Guttman, Peter Lewis, Kevin Riggle,
1075 Ori Avtalion, Torsten Blix, Nigel Metheringham, Gábor Szabó, Tod Hagan,
1076 Michael Hendricks, Ævar Arnfjörð Bjarmason, Piers Cawley, Stephen
1077 Steneker, Elias Lutfallah, Mark Leighton Fisher, Matt Diephouse,
1078 Christian Jaeger, Bill Sully, Bill Ricker, David Golden, Nilson Santos
1079 F. Jr, Elliot Shank, Merijn Broeren, Uwe Voelker, Rick Scott, Ask Bjørn
1080 Hansen, Jerry Gay, Will Coleda, Mike O'Regan, Slaven Rezić, Mark
1081 Stosberg, David Alan Pisoni, Adriano Ferreira, James Keenan, Leland
1082 Johnson, Ricardo Signes, Pete Krawczyk and Rob Hoelz.
1083
1085 Andy Lester, "<andy at petdance.com>"
1086
1088 Copyright 2005-2021 Andy Lester.
1089 This program is free software; you can redistribute it and/or modify it
1091 under the terms of the Artistic License v2.0.
1092 See https://www.perlfoundation.org/artistic-license-20.html or the
1094 LICENSE.md file that comes with the ack distribution.
1095perl v5.32.1 2021-03-13 ACK(1)