Share your knowledge at the LQ Wiki.
Go Back > Forums > Linux Forums > Linux - Software > Linux - Kernel
User Name
Linux - Kernel This forum is for all discussion relating to the Linux kernel.


  Search this Thread
Old 02-20-2007, 03:34 AM   #1
LQ Newbie
Registered: Feb 2007
Location: india
Posts: 2

Rep: Reputation: 0
how to re-initialize user space applications without rebooting

I want to implement warm restart in the embedded linux system: re-initialize user space applications without rebooting - that is, the kernel loaded in the system should remain loaded.
Is there a known mechanism in linux to do that?
FYI, my kernel version is 2.6.5.
In case you need details, let me know.

Old 02-20-2007, 05:04 AM   #2
LQ Newbie
Registered: Jun 2006
Location: Austria
Distribution: RHEL AS 4
Posts: 26

Rep: Reputation: 16
re-initializing applications

Many UNIX system services ("daemons") provide for a mechanism of re-starting themselves. The usual mechanism is through signal handling. Simply send the "SIGHUP", or "1", signal to the process and it will (assuming it has been written this way) restart itself. To send this signal, use the "kill" command.
kill -1 pid
If the daemon does not "handle" the signal in this way, it will likely be killed. In that case, you will need to restart the daemon "by hand".

Some daemons that notably do not restart themselves include:
DHCP (from ISC)
Most "interactive" processes will terminate when you send the HUP signal.
Old 02-20-2007, 06:03 AM   #3
LQ Newbie
Registered: Feb 2007
Location: india
Posts: 2

Original Poster
Rep: Reputation: 0
Great! But my system is as follows:

1. There's only one process in the system and all the applications in the system are as threads in this process.
2. I don't support signal handling!
3. FYI, it's an embedded system - not a desktop one.

Also, even if I succeed to re-init the user space program, how do I re-sync with the kernel again. Is there a standardized technique to do that? Or, I have to do it in a proprietary way.



Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
notify user space application from the kernel space lordofring Linux - Software 2 06-22-2009 12:32 PM
How to share data b/w user space and kernel space nandac Linux - Kernel 1 11-28-2006 10:15 PM
how to run applications as a differnet user? polemon Linux - General 6 07-10-2006 05:13 PM
Access to root applications as a user odiseo77 Fedora 1 02-04-2005 02:29 PM
User Space - Kernel Space basu_arani Programming 3 05-25-2004 11:46 AM > Forums > Linux Forums > Linux - Software > Linux - Kernel

All times are GMT -5. The time now is 08:15 PM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration