capture the output to a variable

Melsync · 09-07-2006, 01:23 PM

I want to assign the value of a certain pid in order to kill it in a script

Quote:

echo `ps ux | grep dhcpcd | grep -v grep` | cut -d' ' -f2`

gets me the pid number, and only that, all right but then

Quote:

pidno=`echo `ps ux | grep dhcpcd | grep -v grep` | cut -d' ' -f2``

returns 'command not found' and

Quote:

pidno="echo `ps ux | grep dhcpcd | grep -v grep` | cut -d' ' -f2`"

returns the whole string of the output of the command ps.
How can I put the single number in a variable?
Thanks.

acid_kewpie · 09-07-2006, 01:27 PM

i'm guessing you've not heard aboput the pidof command?

Code:

pidno=$(pidof dhcpcd)

as far as where you're going wrong... take out all the echo stuff. you need to echo it to show the output as a command but you don't need it to assign the output to a vairable.

Code:

pidno=$(ps ux | ... )

homey · 09-07-2006, 01:51 PM

Other than typo in dhcpd ( dhcpcd ) I would go with

Code:

pidno=$(pidof dhcpd)
echo $pidno
1995

With correct spelling this works also

Code:

pidno=$(echo `ps ux | grep dhcpd | grep -v grep` | cut -d' ' -f2)
echo $pidno
1995

Melsync · 09-07-2006, 02:15 PM

Thank you, all four solutions work.
Btw, homey, the process is not a typo; I'm using this program: dhcpcd at freshmeat
Thanks again.

acid_kewpie · 09-07-2006, 02:17 PM

Quote:

Originally Posted by Melsync

Thank you, all four solutions work.
Btw, homey, the process is not a typo; I'm using this program: dhcpcd at freshmeat
Thanks again.

hehe, bless. dhcpd = dhcp server daemon. dhcpcd = dhcp client daemon.