As reported on the mailing lists in 2012, and resurfaced recently: http://lists.freebsd.org/pipermail/freebsd-current/2012-February/031896.html http://lists.freebsd.org/pipermail/freebsd-stable/2014-September/080172.html Original message below ---- This is -CURRENT of r231204, 9 Feb. xzgrep seems to give up at first read(). $ yes a|head|xz|xzgrep -c a 10 $ yes a|head -100|xz|xzgrep -c a 100 $ yes a|head -10000|xz|xzgrep -c a 10000 $ yes a|head -100000|xz|xzgrep -c a 16384 bzgrep, zgrep and grep works as expected. $ yes a|head|bzip2|bzgrep -c a 10 $ yes a|head -100|bzip2|bzgrep -c a 100 $ yes a|head -1000|bzip2|bzgrep -c a 1000 $ yes a|head -10000|bzip2|bzgrep -c a 10000 $ yes a|head -100000|bzip2|bzgrep -c a 100000 $ yes a|head -1000000|bzip2|bzgrep -c a 1000000 $ yes a|head -10000000|bzip2|bzgrep -c a 10000000 $ yes a|head|gzip|zgrep -c a 10 $ yes a|head -100|gzip|zgrep -c a 100 $ yes a|head -1000|gzip|zgrep -c a 1000 $ yes a|head -10000|gzip|zgrep -c a 10000 $ yes a|head -100000|gzip|zgrep -c a 100000 $ yes a|head -1000000|gzip|zgrep -c a 1000000 $ yes a|head -10000000|gzip|zgrep -c a 10000000 $ yes a|head|grep -c a 10 $ yes a|head -100|grep -c a 100 $ yes a|head -1000|grep -c a 1000 $ yes a|head -10000|grep -c a 10000 $ yes a|head -100000|grep -c a 100000 $ yes a|head -1000000|grep -c a 1000000 $ yes a|head -10000000|grep -c a 10000000 they are single binary (linked statically) $ for f in xzgrep bzgrep zgrep grep; do ls -l $(which $f); done -r-xr-xr-x 15 root wheel 578352 Feb 2 00:39 /usr/bin/xzgrep* -r-xr-xr-x 15 root wheel 578352 Feb 2 00:39 /usr/bin/bzgrep* -r-xr-xr-x 15 root wheel 578352 Feb 2 00:39 /usr/bin/zgrep* -r-xr-xr-x 15 root wheel 578352 Feb 2 00:39 /usr/bin/grep* -- kuro
gjb pointed me to a duplicate. *** This bug has been marked as a duplicate of bug 186861 ***