Hi, For some reason Grep appears to occasionally exit with 0 even when there was no match. This could also be bug Bash, but I wasn't able to reproduce this with other programs, and the failure seems to be more common with some patterns, or pairs of a pattern and an input, which would suggest that the issue is in Grep.
The following is enough to eventually reproduce this on Debian 6.0.4 (x86_64) using the included version (GNU grep 2.6.3) and 2.10 from ftp.gnu.org. The shell is Bash is version 4.1.5(1)-release. $ wget haltp.org/aoh/misc/cout.sh $ while true; do grep RANDOM cout.sh && date; done Nothing should happen, but I'm getting occasional dates as in $ while true > do > grep -q RANDOM tests/cout.sh && date > done Wed Feb 8 05:52:23 EET 2012 Wed Feb 8 06:28:02 EET 2012 and for Grep 2.10 $ while true; do $HOME/opt/grep/bin/grep RANDOM tests/cout.sh && date; done Wed Feb 8 14:56:00 EET 2012 Can anyone reproduce this, and if so, does it look like a Grep thing or something else? -- Aki Helin
