xref: /freebsd-12.1/gnu/usr.bin/grep/README (revision 4441e614)
1*4441e614SRuslan ErmilovThis is GNU grep, the "fastest grep in the west" (we hope).  All
2c18f2d82SPeter Wemmbugs reported in previous releases have been fixed.  Many exciting new
3*4441e614SRuslan Ermilovbugs have probably been introduced in this revision.
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5c18f2d82SPeter WemmGNU grep is provided "as is" with no warranty.  The exact terms
6c18f2d82SPeter Wemmunder which you may use and (re)distribute this program are detailed
7c18f2d82SPeter Wemmin the GNU General Public License, in the file COPYING.
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9c18f2d82SPeter WemmGNU grep is based on a fast lazy-state deterministic matcher (about
10c18f2d82SPeter Wemmtwice as fast as stock Unix egrep) hybridized with a Boyer-Moore-Gosper
11c18f2d82SPeter Wemmsearch for a fixed string that eliminates impossible text from being
12c18f2d82SPeter Wemmconsidered by the full regexp matcher without necessarily having to
13c18f2d82SPeter Wemmlook at every character.  The result is typically many times faster
14c18f2d82SPeter Wemmthan Unix grep or egrep.  (Regular expressions containing backreferencing
15c18f2d82SPeter Wemmwill run more slowly, however.)
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17*4441e614SRuslan ErmilovSee the files AUTHORS and THANKS for a list of authors and other contributors.
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19c18f2d82SPeter WemmSee the file INSTALL for compilation and installation instructions.
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21c18f2d82SPeter WemmSee the file NEWS for a description of major changes in this release.
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23*4441e614SRuslan ErmilovSee the file TODO for ideas on how you could help us improve grep.
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25*4441e614SRuslan ErmilovSend bug reports to [email protected].  Be sure to
26c18f2d82SPeter Wemminclude the word "grep" in your Subject: header field.
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