Fix exit status of xzgrep when grepping binary files.

When grepping binary files, grep may exit before it has
read all the input. In this case, gzip -q returns 2 (eating
SIGPIPE), but xz and bzip2 show SIGPIPE as the exit status
(e.g. 141). This causes wrong exit status when grepping
xz- or bzip2-compressed binary files.

The fix checks for the special exit status that indicates SIGPIPE.
It uses kill -l which should be supported everywhere since it
is in both SUSv2 (1997) and POSIX.1-2008.

Thanks to James Buren for the bug report.

0 files changed, 0 insertions, 0 deletions