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Mail Archives: cygwin/2011/04/19/16:16:58

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Date: Tue, 19 Apr 2011 21:16:37 +0100
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Subject: 0417 snapshot: exec() fails on /proc/self/exe
From: Andy Koppe <andy DOT koppe AT gmail DOT com>
To: cygwin AT cygwin DOT com
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With the latest snapshot, exec() fails on /proc/self/exe:

$ cat test.c
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>

int main(int argc, char *argv[])
{
  if (argc > 1 && !fork()) {
    execl("/proc/self/exe", argv[0], (char *)0);
    puts(strerror(errno));
  }
  return 0;
}

$ cc test.c

$ ./a bla
Bad file descriptor

With 1.7.9, it prints nothing, which is the expected behaviour.
Looking at POSIX, EBADF is not a valid errno for exec().

(The argument in the test is there as a way to stop it from becoming a
fork bomb.)

Andy

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