Probably "just" a matter of adding RE_UNMATCHED_RIGHT_PAREN_ORD into the list for RE_SYNTAX_EGREP in regex.h.
Hmm. Y'all might want to consider basing RE_SYNTAX_POSIX_EGREP off of RE_SYNTAX_POSIX_EXTENDED; that would have gotten this case. (Lordy, lordy, lordy, do I hate the syntax bits.) HTH, Arnold Nathan Weeks <we...@iastate.edu> wrote: > GNU grep 2.20 disallows the use of an unmatched right parenthesis in > an extended regular expression: > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > $ echo ')' | grep -E ')' > grep: Unmatched ) or \) > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Other greps I've tried (AST grep 2014-01-06, BusyBox 1.22.1 grep, BSD > grep 2.5.1-FreeBSD on OS X 10.8, /usr/xpg4/bin/grep on Solaris > 11.2-beta) accept ')' as a valid ERE. > > POSIX apparently allows an unmatched right parenthesis in this > context, as section 9.4.3 (ERE Special Characters; > http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_04_03) > states: > > "The <right-parenthesis> shall be special when matched with a preceding > <left-parenthesis>, both outside a bracket expression." > > and in section 9.5.1 (BRE/ERE Grammar Lexical Conventions) > (http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_05_01), > the description of the "SPEC_CHAR" token contains the following > exception: > > "The close-parenthesis shall be considered special in this context only if > matched with a preceding open-parenthesis." > > -- > Nathan Weeks > IT Specialist > USDA-ARS Corn Insects and Crop Genetics Research Unit > Crop Genome Informatics Laboratory > Iowa State University > http://weeks.public.iastate.edu/ > >
