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Mail Archives: cygwin-developers/2000/02/28/10:51:16

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Message-ID: <779F20BCCE5AD31186A50008C75D99791716E9@SILLDN_MAIL1>
From: "Fifer, Eric" <EFifer AT sanwaint DOT com>
To: "'cygwin-developers AT sourceware DOT cygnus DOT com'"
<cygwin-developers AT sourceware DOT cygnus DOT com>
Subject: wait not setting errno to EINTR when interrupted
Date: Mon, 28 Feb 2000 15:59:19 -0000
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With the Feb-27 I'm seeing a interrupted wait() not setting errno to EINTR.

This is an example:

#include <unistd.h>
#include <stdio.h>
#include <sys/wait.h>
#include <signal.h>
#include <errno.h>

int onalrm() { printf("onalrm\n"); }

main()
{
    pid_t pid;
    int status = 0;

    if(fork() == 0) {
        sleep(10);
        exit(37);
    }

    signal(SIGALRM, onalrm);
    alarm(3);
    pid = wait(&status);
    printf("pid=%d status=%d errno=%d\n", pid, status, errno);
}

A run shows:

% ./a.exe
onalrm
pid=-1 status=0 errno=10

errno should be 4 (EINTR), *not* 10 (ECHILD, No Children).

I've attached a fix that works, but I'm not certain it is correct.

Eric



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	name="wait.patch"
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	filename="wait.patch"

--- sigproc.cc-	Mon Feb 28 12:23:28 2000=0A=
+++ sigproc.cc	Mon Feb 28 15:48:56 2000=0A=
@@ -354,9 +354,10 @@ proc_subproc (DWORD what, DWORD val)=0A=
 	    {=0A=
 	      sip_printf ("waiting thread found no children");=0A=
 	      HANDLE oldw =3D w->next->ev;=0A=
-	      w->next->ev =3D NULL;=0A=
 	      if (clearing)=0A=
 		w->next->status =3D -1;		/* flag that a signal was received */=0A=
+	      else=0A=
+	        w->next->ev =3D NULL;=0A=
 	      if (!SetEvent (oldw))=0A=
 		system_printf ("couldn't wake up wait event %p, %E", oldw);=0A=
 	      w->next =3D w->next->next;=0A=

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