10-23-2007
Yes, there is: put a cron-job in effect, which truncates the file (by something like "cat /dev/null > nohup.out"). How often you will have to run this job depends on how much output your process generates.
But if you do not need the output of the job altogether (maybe its garbage anyways, only you can answer that) you could prevent writig to file nohup.out in first place. Right now you start the process in a way like this:
nohup command &
replace this by
nohup command 2>/dev/null 1>/dev/null &
and the file nohup.out won't even get created.
The reason why the output of the process is being directed to a file is:
Normally all processes (that is: commands you enter from commandline, there are exceptions, but they don't matter here) are attached to a terminal. Per default (this is how Unix is handling this) this is something which can display text and is connect to the host via a serial line. If you enter a command and switch off the terminal you entered it from the process gets terminated too - because it lost its terminal. Because in serial communication the technicians traditionally employed the words from telephone communication (where it came from) the termination of a communication was not called an "interruption" or "termination" but a "hangup". So programs got terminated on "hangups" and to program to prevent this was "nohup", the "no-termination-upon-hangup"-program.
But as it may well be that such an orphaned process has no terminal to write to it nohup uses the file nohup.out as a "screen-replacement", redirecting the output there, which would normally go to the screen. If a command has no output whatsoever though nohp.out won't get created.
bakunin
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