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From: Chris Faylor <cgf AT cygnus DOT com>
Date: Fri, 15 Sep 2000 11:30:36 -0400
To: cygwin-developers AT sourceware DOT cygnus DOT com
Subject: Re: EINTR after SIGSTOP/SIGCONT
Message-ID: <20000915113036.A4739@cygnus.com>
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References: <18275375909 DOT 20000915165822 AT logos-m DOT ru>
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In-Reply-To: <18275375909.20000915165822@logos-m.ru>; from deo@logos-m.ru on Fri, Sep 15, 2000 at 04:58:22PM +0400

Cygwin does not have "restartable" I/O.  That means that reads on
"slow" devices like pipes or ttys will be interrupted by a signal.

cgf

On Fri, Sep 15, 2000 at 04:58:22PM +0400, Egor Duda wrote:
>Hi!
>
>  this program:
>
>===================================================================
>#include <errno.h>
>#include <stdio.h>
>#include <signal.h>
>
>int main ( int argc, char** argv )
>{
>  char buf[10];
>  int pid;
>  int a[2];
>  int rc;
>
>  pipe ( a );
>  pid = fork ();
>  if ( pid == 0 )
>    {
>      rc = read ( a[0], buf, 1 );
>      if ( rc < 0 ) perror ( "error reading from pipe" );
>    }
>  else  
>    {
>      kill ( pid, SIGSTOP );
>      sleep(1);
>      kill ( pid, SIGCONT );
>      sleep(1);
>      write ( a[1], buf, 1 );
>      waitpid ( pid );
>    }
>}
>===================================================================
>
>prints `error reading from pipe: Interrupted system call' on cygwin
>and  none  on linux. is it intended behavior, or cygwin shouldn't post
>"signal_arrived" event on SIGCONT signal?
>
>Egor.            mailto:deo AT logos-m DOT ru ICQ 5165414 FidoNet 2:5020/496.19
>

-- 
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