Sed is fixed in plan9port. $ hg diff sed.c diff -r 478b53880a80 src/cmd/sed.c --- a/src/cmd/sed.c Wed Feb 04 20:12:48 2009 -0800 +++ b/src/cmd/sed.c Wed Feb 04 20:13:08 2009 -0800 @@ -994,7 +994,7 @@ return 0; subexp[0].s.rsp = buf; subexp[0].e.rep = 0; - if (rregexec(pattern, linebuf, subexp, MAXSUB)) { + if (rregexec(pattern, linebuf, subexp, MAXSUB) > 0) { loc1 = subexp[0].s.rsp; loc2 = subexp[0].e.rep; return 1; $
http://hg.pdos.csail.mit.edu/hg/plan9/rev/0bf86c524c9b