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   <H1>[IRCServices Coding] Crontab Script</H1>
    <B>V13</B> 
    <A HREF="mailto:ircservices-coding%40ircservices.za.net?Subject=%5BIRCServices%20Coding%5D%20Crontab%20Script&In-Reply-To=c3.23367af9.2a20c919%40aol.com"
       TITLE="[IRCServices Coding] Crontab Script">v13 at it.teithe.gr
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    <I>Sun Jun  2 05:37:03 PDT 2002</I>
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<PRE> Andrew, I suppose you can include/use the attached code (or any modified 
version of it) in services, without causing portability problems. It will 
solve the pidfile problem and the need of a keepalive script. It just creates 
and locks the pidfile using an advisory lock. This way it stays locked while 
services are running. OS will unlock it if services die. I'm currently using 
it in some progs of mine without any problems. It seems to compile and work 
on linux, freebsd, irix and solaris without problems. Since this is a 
modified version of the one i'm using, this may be incorect.

 There are 3 functions. pidfile_islocked(), pidfile_dolock(), 
pidfile_dounlock(). That check for a lock, lock and unlock the pidfile. They 
also create and remove the pidfile. I'm also using pidfile_islocked to get 
the current pid of the running copy. This way I can kill the running copy 
when the program is run with (for exampe) '-k' by 

pid=pidfile_islocked(PIDFILE);
if (pid)
	kill(pid,SIGTERM);

 In case of fork(), you have to call pidfile_islocked() once before the fork() 
is done and pidfile_dolock() after the fork, so that the lock will not go 
away. I'm attaching an example program too.

 There exists a race condition, but i prefer this from the one that exist in 
every keepalive script.

&lt;&lt;V13&gt;&gt;
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	14	<H1>[IRCServices Coding] Crontab Script</H1>
	15	<B>V13</B>
	16	<A HREF="mailto:ircservices-coding%40ircservices.za.net?Subject=%5BIRCServices%20Coding%5D%20Crontab%20Script&In-Reply-To=c3.23367af9.2a20c919%40aol.com"
	17	TITLE="[IRCServices Coding] Crontab Script">v13 at it.teithe.gr
	18	</A><BR>
	19	<I>Sun Jun 2 05:37:03 PDT 2002</I>
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	33	<!--beginarticle-->
	34	<PRE> Andrew, I suppose you can include/use the attached code (or any modified
	35	version of it) in services, without causing portability problems. It will
	36	solve the pidfile problem and the need of a keepalive script. It just creates
	37	and locks the pidfile using an advisory lock. This way it stays locked while
	38	services are running. OS will unlock it if services die. I'm currently using
	39	it in some progs of mine without any problems. It seems to compile and work
	40	on linux, freebsd, irix and solaris without problems. Since this is a
	41	modified version of the one i'm using, this may be incorect.
	42
	43	There are 3 functions. pidfile_islocked(), pidfile_dolock(),
	44	pidfile_dounlock(). That check for a lock, lock and unlock the pidfile. They
	45	also create and remove the pidfile. I'm also using pidfile_islocked to get
	46	the current pid of the running copy. This way I can kill the running copy
	47	when the program is run with (for exampe) '-k' by
	48
	49	pid=pidfile_islocked(PIDFILE);
	50	if (pid)
	51	kill(pid,SIGTERM);
	52
	53	In case of fork(), you have to call pidfile_islocked() once before the fork()
	54	is done and pidfile_dolock() after the fork, so that the lock will not go
	55	away. I'm attaching an example program too.
	56
	57	There exists a race condition, but i prefer this from the one that exist in
	58	every keepalive script.
	59
	60	<<V13>>
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65	Size: 301 bytes
66	Desc: not available
67	Url : <A HREF="../attachments/20020602/3c6a97c2/example.c">../attachments/20020602/3c6a97c2/example.c</A>
68	-------------- next part --------------
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70	Name: pidfile.c
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73	Desc: not available
74	Url : <A HREF="../attachments/20020602/3c6a97c2/pidfile.c">../attachments/20020602/3c6a97c2/pidfile.c</A>
75	</PRE>
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