I have a script that does some stuff in a tight loop and than sleeps at the end of each loop for an unpredicatable amount of time (few seconds to few minutes).

(A) I want it to run continuously in the background

(B) I don't want to accidentally run two of them at the same time.

(C) I want it to automatically come back alive after system boot.

(D) It might accidentally get killed, so I want it to be able to tollerate that.

My guesses are as follows:

? Open a dummy lock file when the script starts and don't close it? Die if you cant open it? Code for this? open or die?

? Edit some kind of file in my /home/andrew directory that gets automatically executed and run it with a trailing &? to run in the background.

Will this satisfy the above requirements?

Update: It's not a networking or IP related program. Sorry, the daemon title through you off. I meant it in the sense of a program that stays uniquely alive. I guess daemon's accepted meaning is something small that listens on a port like daytime or ntp - this is not what I mean.

-Andrew.

Andrew Tomazos  |  andrew@tomazos.com  |  www.tomazos.com

In reply to Writing a Perl Daemon by tomazos

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