topic Re: removing the last character from fuser in Operating System - Linux

removing the last character from fuser

lawrenzo_1 — Fri, 26 Oct 2007 08:36:14 GMT

Hello,

I am working on AIX and run fuser, I get several procs with 1234c 234344c 34445c

how can I script to loose the last character, I'd like to know how to drop any final character for otheer scripting purposes.

Thanks for your help!

Chris.

Re: removing the last character from fuser

James R. Ferguson — Fri, 26 Oct 2007 08:53:04 GMT

Hi Chris:

You could do something like this:

# echo "abc123"|awk '{print substr $0,0,length($0)-1)}'

abc12

This trims the last character of any string.

In Perl:

# echo "abc123"|perl -ple 'chop'
abc12

Regards!

...JRF...

Re: removing the last character from fuser

Jeff_Traigle — Fri, 26 Oct 2007 08:56:18 GMT

The following will work for your specific case. You can't just drop the last character because it's possible to have multiple letters after the PID in fuser output. The first regexp eliminates the alpha characters (leaving the PIDs and a mangled path) and the second regexp eliminates the mangled path (leaving only the PIDs as the final output).

fuser -c /data 2>&1 | sed -e 's/[a-z]//g' -e 's/[^0-9[:blank:]]//g'

Re: removing the last character from fuser

Ralph Grothe — Fri, 26 Oct 2007 09:05:07 GMT

Funny, the others haven't observed this.
Simply redirect stderr to /dev/null.
This strips everything apart from the PIDs.

e.g.

# fuser -c /oracle 2>/dev/null
15385 15488 15392 15487 15405 15388 15407 12205 15418 15406 15410 15420
15372 2676 15404 15386

This is handy if you want to use the PIDs in situ.

# ps -p "$(fuser -c /oracle 2>/dev/null)"
ps: wrong PID number
PID TTY TIME COMMAND
15385 ? 430:55 disp+work
15488 ? 533:41 jlaunch
15392 ? 11:15 disp+work
15487 ? 84:04 jlaunch
15405 ? 0:05 disp+work
15388 ? 595:17 disp+work
15407 ? 0:03 disp+work
12205 ? 3:39 disp+work
15418 ? 6:15 disp+work
15406 ? 0:00 disp+work
15410 ? 0:00 disp+work
15420 ? 0:00 disp+work
15372 ? 7:00 disp+work
2676 ? 0:00 disp+work
15404 ? 1:35 disp+work
15386 ? 49:07 disp+work

Re: removing the last character from fuser

Jeff_Traigle — Fri, 26 Oct 2007 09:06:56 GMT

I almost did... I just wasn't awake enough yet to realize it. :)

Re: removing the last character from fuser

James R. Ferguson — Fri, 26 Oct 2007 09:25:55 GMT

Hi (again) Chris:

Thanks, Ralph, I too remembered that when I actually executed 'fuser'.

By the way, Chris, Perl allows a negative value for the length parameter to 'substr'. Using a negative value for length trims that many characters from the end. For example:

# echo abc123|perl -nle 'print substr($_,0,-1)'

abc12

Thus, there's yet another way to do this.

Regards!

...JRF...

Re: removing the last character from fuser

lawrenzo_1 — Fri, 26 Oct 2007 10:23:14 GMT

ok thanks again chaps,

as always plenty of ways of killing a bird with many stones!

:-)

Chris.