This is strange. I want only to grep line containing /run. But it returning other lines too.
[root@s5 ~]# df -h | grep -w "tm" [root@s5 ~]# df -h | grep -w "tmpfs" tmpfs 489M 0 489M 0% /dev/shm tmpfs 489M 6.8M 483M 2% /run tmpfs 489M 0 489M 0% /sys/fs/cgroup tmpfs 98M 0 98M 0% /run/user/1001 tmpfs 98M 0 98M 0% /run/user/0 [root@s5 ~]# df -h | grep -w "tmpf" [root@s5 ~]# df -h | grep -w "/run" tmpfs 489M 6.8M 483M 2% /run tmpfs 98M 0 98M 0% /run/user/1001 tmpfs 98M 0 98M 0% /run/user/0 -w, --word-regexp Select only those lines containing matches that form whole words. The test is that the matching substring must either be at the beginning of the line, or preceded by a non-word constituent character. Similarly, it must be either at the end of the line or followed by a non-word constituent character. Word-constituent characters are letters, digits, and the underscore.
Works as expected, I say. If your intention is to get only the first match you should use
$ df -h | grep -w "/run$" 