LinuxQuestions.org
Review your favorite Linux distribution.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Newbie
User Name
Password
Linux - Newbie This Linux forum is for members that are new to Linux.
Just starting out and have a question? If it is not in the man pages or the how-to's this is the place!

Notices


Reply
  Search this Thread
Old 02-21-2009, 11:48 PM   #1
palisetty_suman
Member
 
Registered: Feb 2007
Location: TX, USA
Distribution: fedora
Posts: 191

Rep: Reputation: 33
Thumbs up Sighup


Hi can anybody say about SIGHUP signal. I read its for hangup but i didnot understand whats meant by that. Pls tell me in very simple sense. Pls don't refer me to any website. I want our knowledge because its easier to learn from u than from website. Thanks.
 
Old 02-22-2009, 12:16 AM   #2
JulianTosh
Member
 
Registered: Sep 2007
Location: Las Vegas, NV
Distribution: Fedora / CentOS
Posts: 674
Blog Entries: 3

Rep: Reputation: 90
it's a method for the OS and other programs to send specific signals between each other. SIGHUP is basically like a "I'm asking you nicely to quit" message.

Here's some other examples of Linux Signals:
http://www.comptechdoc.org/os/linux/...pgsignals.html
 
Old 02-22-2009, 06:36 AM   #3
alan_ri
Senior Member
 
Registered: Dec 2007
Location: Croatia
Distribution: Debian GNU/Linux
Posts: 1,733
Blog Entries: 5

Rep: Reputation: 127Reputation: 127
There's something interesting if you would like to know;SIGHUP can be intercepted and handled,like all SIG signals except SIGKILL and SIGSTOP.
 
Old 02-22-2009, 07:08 AM   #4
chrism01
LQ Guru
 
Registered: Aug 2004
Location: Sydney
Distribution: Centos 6.9, Centos 7.3
Posts: 17,417

Rep: Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397
It originally dates from the old days, when everything was dial-up (eg ARPANet, precursor to internet).
It literally means hang-up the phone line, which is why you use

nohup prog

to ensure a prog keeps running when you logout, otherwise it dies, because its still attached to the terminal session, even if you use '&'. '&' only puts it in the background, its still connected to your term session.
These days SIGHUP is in fact usually used to get a prog eg Apache to re-read its config file on the fly ie without an explicit re-start.

HTH
 
  


Reply


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
SIGHUP / kill -1 SlowCoder Linux - General 6 01-30-2008 07:38 PM
Sending SIGHUP to inetd glansing Linux - Newbie 3 09-16-2005 03:13 AM
How inetd gets sighup? rajesh_b Programming 1 09-17-2004 05:38 AM

LinuxQuestions.org > Forums > Linux Forums > Linux - Newbie

All times are GMT -5. The time now is 02:04 AM.

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