"watch" command

GiotisSL · 03-06-2008, 07:16 AM

hello Guys,
Can anyone help me with the "watch" command in Linux CentOS ?
I want to watch a user in my server.
I have full root access.

In FreeBSD the command is "watch -W pid#"

example:
ps aux
(the user's pid number is 1234)
# watch -W 1234

Is there a similar command in linux ?

BrianK · 03-06-2008, 02:22 PM

Not so similar on the command side, but similar on the result side:

watch "ps aux | grep <pid> | grep -v grep"

GiotisSL · 03-07-2008, 07:00 AM

I see nothing.

<<<
# ps aux
(pid# is 8558 and 8560)
# watch ps aux | grep 8558 | grep -v grep
#
[1]+ Stopped watch ps aux | grep 8558 | grep -v grep
# watch ps aux | grep 8560 | grep -v grep
#

Every 2.0s: ps aux | grep 8558 | grep -v grep Fri Mar 7 13:58:39 2008

root 8558 0.0 0.0 9008 2636 ? Ss 13:52 0:00 sshd: admin [priv]
>>>

Is there any command which I can see what a user is doing in real time ?
I mean when the user type "hello", my shell show me that the user type "hello".

BrianK · 03-07-2008, 04:04 PM

Quote:

Originally Posted by GiotisSL

quotes are important.

watch ps aux | grep 8560 | grep -v grep

is not the same as

watch "ps aux | grep 8560 | grep -v grep"

... in the former, you're grepping the watch output. In the latter, you're grepping the ps output. So your example will do nothing. With quotes, you will see what you're looking for.

Quote:

Is there any command which I can see what a user is doing in real time ?
I mean when the user type "hello", my shell show me that the user type "hello".

This I don't know about, it doesn't seem reasonable (in that - what are you looking for? keystrokes? completed commands?, running programs?), but there's probably a way of doing something similar. :shrug:

anomie · 03-07-2008, 09:37 PM

Quote:

Originally Posted by GiotisSL

Can anyone help me with the "watch" command in Linux CentOS ?
...
In FreeBSD the command is "watch -W pid#"

FreeBSD watch is very different than CentOS watch. AFAIK, they are not related and the naming is a coincidence.

FBSD: watch -- snoop on another tty line
CentOS: watch -- execute a program periodically, showing output fullscreen

The latter is akin to running an arbitrary command in a while loop. (And I don't know an analogous command for FBSD's watch in CentOS.)

GiotisSL · 03-09-2008, 06:51 AM

Is there any similar/same command ?

gbellini · 04-10-2008, 04:15 AM

HI all,

digging around I found ttysnoop (www linuxhelp net guides ttysnoop)
I've not tried it yet, but I think it's worth a try

Cheers

amrahd · 04-11-2008, 01:16 PM

Yeah, here's a page describing how to get ttysnoop working on linux:

(add the http: / / bit before the following URL - this lame board wouldn't let me have a URL in my first post.)

sysadmingear.blogspot.com/2007/10/how-to-install-ttysnoop-on-linux.html

..and I was busy looking for a way to get the linux 'watch' command for freebsd - looks like someone else already took care of that: 'cmdwatch' tho I supose not many people on this board will care.

take care,
amrahd

Quote:

Originally Posted by gbellini

HI all,

digging around I found ttysnoop (www linuxhelp net guides ttysnoop)
I've not tried it yet, but I think it's worth a try

Cheers