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Stop process while running script

Hi everyone,

I am trying to get some information out of mplayer. I want to know the length of a video file. I used "-identify" switch it returns a whole bunch of information including something called "ID_LENGTH" which is exactly what I need. Here is what I do in the bash script. (I pass the name of the video file as an argument to the script)

Code:

mplayer -identify "$1" 2> /dev/null | grep "ID_LENGTH" > /tmp/out.$$

cat /tmp/out.$$ | cut -d"="  -f2,2

This actually returns the value that I need to get, but the problem is that I need to stop mplayer by hand. The output when I run the script should be the length of the file, without really running the file, so we should exit from mplayer as soon as we get "ID_LENGTH" field so that the script will continue and the length of the file will be outputed on the stdout.

Thanx in advance

You could run the mplayer process in the background and then use "kill -SIGQUIT %1" to kill it.

Code:

mplayer -identify "$1" 2> /dev/null | grep "ID_LENGTH" > /tmp/out.$$ &

sleep 5

cat /tmp/out.$$ | cut -d"="  -f2,2

kill -SIGQUIT %1

I don't know if 5 seconds is enough time to locate the video.