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From: dkeisen@Gang-of-Four.Stanford.EDU (Dave Eisen)
Newsgroups: comp.unix.questions
Subject: Re: what the kill() system call should do??
Message-ID: <1990Sep28.174450.4935@Neon.Stanford.EDU>
Date: 28 Sep 90 17:44:50 GMT
References: <25784.2700d355@kuhub.cc.ukans.edu>
Sender: news@Neon.Stanford.EDU (USENET News System)
Organization: Sequoia Peripherals
Lines: 32

In article <25784.2700d355@kuhub.cc.ukans.edu> jian@kuhub.cc.ukans.edu writes:
>
>I tried to send a signal (SIGUSR1) from a child process to its parent process
>by using kill() system call in C. The result was funny. Whenever the parent
>process received the signal, it died immediately. I don't know what goes wrong
>in my program. Any help appreciated.
>
>void parent_process()
>{
>  int ppid;
>  ....
>
>  switch( pid = fork()) {

  ......
>    
>     default:   
>       signal(SIGUSR1, catch_usr1);
>  }
>

The child can post the signal to the parent before the parent returns from
the fork, if this happens the default action (termination) will occur.
Set up the signal handler before the fork.



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