Penguin

Differences between current version and revision by previous author of SIGHUP.

Other diffs: Previous Major Revision, Previous Revision, or view the Annotated Edit History

Newer page: version 11 Last edited on Saturday, July 23, 2005 1:23:41 pm by AristotlePagaltzis
Older page: version 10 Last edited on Wednesday, June 15, 2005 11:31:49 pm by MichaelJager Revert
@@ -1,15 +1,25 @@
-!!!Signal: Hangup 
+!!! Signal: Hangup 
  
-This signal is generated by the kernel when your controlling terminal goes away to the terminals ProcessGroup. Or, in simplier terms, when you close the Xterm, or hang up a modem. Since daemons run in the background and don't have a controlling terminal, they often use SIGHUP to signal that they should reread their configuration files. This can cause issues with some programs that work as both a daemon and an interactive program, such as fetchmail(1).  
-An example of a daemon that rereads it's configuration file on SIGHUP is init(8), the first process created (which is responsible for creating all other processes, like getty for logging in). If you edit /etc/ inittab, its configuration file, you can do 
+This signal is generated by the [Kernel] when your controlling terminal goes away to the terminals ProcessGroup. Or, in simplier terms, when you close the Xterm, or hang up a modem. Since daemons run in the background and don't have a controlling terminal, they often use [ SIGHUP] to signal that they should reread their configuration files. This can cause issues with some programs that work as both a daemon and an interactive program, such as fetchmail(1).  
+  
+An example of a daemon that rereads its configuration file on [ SIGHUP] is init(8), the first process created (which is responsible for creating all other processes, like getty for logging in). If you edit inittab(5) , its configuration file, you can do  
+  
+ <verbatim>  
  kill -HUP 1 
+ </verbatim>  
+  
 and it will re-read the config file (note that the correct way to do this is to use [telinit(8)]). 
  
-To restart an inetd(8) service, you find inetd's ProcessId and send a hangup to it:  
- kill -HUP { inetd_pid}  
+To restart an inetd(8) service, you find its [PID] and send a [SIGHUP] to it:  
+  
+ <verbatim>  
+ kill -HUP $ inetd_pid  
+ </verbatim>  
+  
+You can prevent a process from recieving a [SIGHUP] signal by using the command nohup(1), for example:  
  
-You can prevent a process from recieving a SIGHUP signal by using the command nohup(1)  
+ <verbatim>  
+ nohup wget http://www.example.com/ &  
+ </verbatim>  
  
-For example:  
- nohup wget http://www.example.com/ &  
- will run " wget" that is not attached to a terminal (and therefore doesn 't recieve a SIGHUP) when you disconnect. This is useful if the file you are downloading is long, but you want to logout before the download is complete. The " &" at the end is used to put the command into the background. 
+will run wget(1) detached from the terminal, so it won 't recieve a [ SIGHUP] when you disconnect. This is useful if a download is so large that you want to log out instead of waiting until it is complete. ( The <tt> &</tt> is [Shell] lingo to put the command into the background so that you can do something else, such as, uh, logging out .)