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nDray

Member

From: Portugal

Registered: 2007-01-21

Posts: 143

Website

send script to background

Hi everyone.

I have made a script to keep a mirror of a local folder to an ftp. It works, but now I want it to run as a daemon, in the background.
Question is, how do I do that? How do I send a process to the background?

I'm looking to putting it in /etc/rc.d/ ...

Thanks in advance.

Dusty

Schwag Merchant

From: Medicine Hat, Alberta, Canada

Registered: 2004-01-18

Posts: 5,986

Website

Re: send script to background

Take a look at some of the other daemons in /etc/rc.d for a template.

Specifically to start a script in the background, append a & to the line. For example:

$ firefox &

will start firefox in the background and allow you to type new commands in the terminal. You can also press CTRL-Z while a program is running and then type 'bg' to send the task to the background. To get a listing of currently running backgrounded programs, type 'jobs'

Dusty

---

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peets

Member

From: Montreal

Registered: 2007-01-11

Posts: 936

Website

Re: send script to background

"In the background" is a funny expression. The way I see it, everything runs in the background, and some programs are used to get some insight about what's going on in the background (shells and X clients). I wish more people saw things this way...

Anyway, you can write a little file in /etc/rc.d that will call your script (like Dusty said, follow the templates). It will be run headless, "in the background," upon boot (if you put the name of that little file in your DAEMONS array in /etc/rc.conf), or you can start in manually by calling

/etc/rc.d/$your_little_file start

.

Take a look at /etc/rc.multi (I think that's what it's called... can't check right now) to understand what's going on. (It's one of those executable files in /etc, and it has 'multi' in its name. It's the startup script responsible for launching what's given in the DAEMONS array)

nDray

Member

From: Portugal

Registered: 2007-01-21

Posts: 143

Website

Re: send script to background

Ok, but that "background" is a little different...
The way the daemons under /etc/rc.d are started is a little different....
They call processes that are daemons by themselves... If I call the script normally, the caller will wait for the script to finish and return something.

On the other hand, if I call it with &, it is supposed to die when the caller finishes, or sometime later, isn't it, because it's a child process?

should i use nohup?

Last edited by nDray (2008-03-05 21:13:48)

Dusty

Schwag Merchant

From: Medicine Hat, Alberta, Canada

Registered: 2004-01-18

Posts: 5,986

Website

Re: send script to background

Wow, T-Dawg is back! Beers all round!

Dusty

---

** Arch Linux Apparel and more ** Arch Linux stickers, laptop bags, jewelery ** I wrote a book on Python 3 ** and one on mental health **

T-Dawg

Forum Fellow

From: Charlotte, NC

Registered: 2005-01-29

Posts: 2,736

Re: send script to background

who?
mwuhahahah....

peets

Member

From: Montreal

Registered: 2007-01-11

Posts: 936

Website

Re: send script to background

wot? I'm too young for this. I'll gladly accept the beer though (I'm not that young ).

Anyway, here's some suggestions. I'm not a process-expert at all.

1. Post your script online man!
2. use cron? (if your script is not meant to go on forever)
3. use exec? (your terminal process will be replaced by the script)

nDray

Member

From: Portugal

Registered: 2007-01-21

Posts: 143

Website

Re: send script to background

i just used &, it seems to work...