Can someone point me to a reference that would explain what a daemon is and is not and compare and contrast a daemon to crontab and cron jobs? I stumbled around google and found a whole lot of nothing and my O'Reilly Web Design and Unix in a Nutshell don't mention daemons.
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Rob

SW Montana's Online Community
Modular Model Railroading

Daemon is a background process (pronounced "demon") that carries out tasks on behalf of every user. Daemons spend most of their time sleeping until something comes along which requires their help. A UNIX system has a lot of daemons.

These mainly sleep until they get disturbed by us users <g> and called into action. Think of a printer queue on your computer. The spool sleeps until you provoke it and then it starts up and does it's job.

At least, that's my understanding of the subject.

- wil

In the docs I was able to find, it talked about daemons being set up as cron jobs. Does a daemon have to be set up as a cron job, or can it be set up another way?
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Rob

SW Montana's Online Community
Modular Model Railroading

No. Cron is a daemon. It is a program constantly running in the background, that comes to life when needs to. Daemons constantly monitor the system, and if something needs doing it springs to life.

A good example is cron, mail (especially SMTP), news, print etc. They constantly monitor the system, and always active, but sleeping or dormant.

Cheers

- wil