1 Copyright (C) 1992, 1997-2002, 2004-2020 Free Software Foundation, Inc. 2 3 Copying and distribution of this file, with or without modification, 4 are permitted in any medium without royalty provided the copyright 5 notice and this notice are preserved. 6 7This is GNU grep, the "fastest grep in the west" (we hope). All 8bugs reported in previous releases have been fixed. Many exciting new 9bugs have probably been introduced in this revision. 10 11GNU grep is provided "as is" with no warranty. The exact terms 12under which you may use and (re)distribute this program are detailed 13in the GNU General Public License, in the file COPYING. 14 15GNU grep is based on a fast lazy-state deterministic matcher (about 16twice as fast as stock Unix egrep) hybridized with a Boyer-Moore-Gosper 17search for a fixed string that eliminates impossible text from being 18considered by the full regexp matcher without necessarily having to 19look at every character. The result is typically many times faster 20than Unix grep or egrep. (Regular expressions containing back-references 21will run more slowly, however.) 22 23See the files AUTHORS and THANKS for a list of authors and other contributors. 24 25See the file INSTALL for compilation and installation instructions. 26If there is no INSTALL file, this copy of the source code is intended 27for expert hackers; please see the file README-hacking. 28 29See the file NEWS for a description of major changes in this release. 30 31See the file TODO for ideas on how you could help us improve grep. 32 33See the file README-alpha for information on grep development and the CVS 34 repository. 35 36Send bug reports to bug-grep@gnu.org. 37 38KNOWN BUGS: 39 40Several tests in fmbtest.sh and foad1.sh fail under the cs_CZ.UTF-8 locale 41and have been disabled. 42 43The combination of -o and -i options is broken and the known failing cases 44are disabled in foad1.sh 45 46The option -i does not work properly in some multibyte locales such as 47tr_TR.UTF-8 where the upper case and lower case forms of a character are not 48necessarily of the same byte length. 49 50A list of outstanding and resolved bugs can be found at: 51 52 https://debbugs.gnu.org/cgi/pkgreport.cgi?package=grep 53 54You can also browse the bug-grep mailing list archive at: 55 56 https://lists.gnu.org/r/bug-grep/ 57 58For any copyright year range specified as YYYY-ZZZZ in this package 59note that the range specifies every single year in that closed interval. 60