Watching some video tutorials I notice sometimes tutors type in stuff similar to this way too often:
ps -e | grep 42
This is being done for finding if process with PID 42 is still being run, for
e. g.. What’s really should be used instead is
ps alone (not to mention
fgrep instead of
If you want to remember it, you’d better give it a try now:
ps 1 – you
always can expect to have
init process running and by convention it’s PID 1.
As can be seen (and remembered)
ps alone can give you info about specified PID,
and this is quite portable feature, it works the same way on Linux, FreeBSD,
Mac OS X and you-name-it.
grep still makes sense when searching by name indeed. It has own
drawbacks, namely finding itself too but that’s something you can workaround
with a clever old trick – just use square brackets:
ps -e | grep 'syslo[g]'
ps -e | grep syslog
syslo[ doesn’t match pattern
syslo[g]. Of course if you were looking
for something with
grep in name, this trick won’t do and this could be the
time to use