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Date:      Wed, 14 Oct 1998 09:01:30 -0700
From:      Mike Smith <mike@smith.net.au>
To:        Darren Whittaker <djw@sage1.sagecorp.com>
Cc:        Mike Smith <mike@smith.net.au>, freebsd-current@FreeBSD.ORG, john.young@openmarket.com
Subject:   Re: problem in 3.0 
Message-ID:  <199810141601.JAA01049@dingo.cdrom.com>
In-Reply-To: Your message of "Wed, 14 Oct 1998 08:12:03 MDT." <Pine.SOL.3.93.981014080742.8720A-100000@sage1.sagecorp.com> 

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> Thank you for your email. I have taken your code and modified it to run as
> a cgi:
> 
> #include <stdio.h>
> #include <err.h>
> #include <errno.h>
> 
> int main(int argc, char *argv[])
> {
>   int     i, j;
>   char    buf[256];
>   FILE    *p;
> 
> /* output the head */
>   printf("Content-type: text/html\n");
>   fflush(stdout);
>   printf("\n<html><head><title>TESTING</title></head>");
>   printf("<CENTER><H1>TESTING</CENTER></H1><HR>\n");
>   printf("<body bgcolor=#ffffff><p><pre>\n");
>   fflush(stdout);
> 
> /* loop using popen */
>   for (i = 0; i < 10; i++)
>   {
>      buf[0] = '\0';
>      if ((p = popen("/bin/date", "r")) == NULL)
>      {
>        printf("popen error: %s\n",strerror(errno));
>        continue;
>      }
>      fgets(buf, sizeof(buf) - 1, p);
>      printf(buf);
> 
>      if ((j = pclose(p)) != 0)
>        printf("pclose error: %s [%d]\n",strerror(j),j);

This is incorrect; it should read

      if (pclose(p) == -1)
        printf("pclose error: %s [%d]\n", strerror(errno), errno);

See the manpage for pclose().

> Here is some of the output when I run it from the web browser:
> 
> Wed Oct 14 07:00:13 PDT 1998
> pclose error: No child processes [10]
...
> What do you think the problem might be?

A return value of 10 from pclose() is not an error; it's the exit code 
of the child process.  /bin/date does not appear to reliably set its 
exit code.

-- 
\\  Sometimes you're ahead,       \\  Mike Smith
\\  sometimes you're behind.      \\  mike@smith.net.au
\\  The race is long, and in the  \\  msmith@freebsd.org
\\  end it's only with yourself.  \\  msmith@cdrom.com



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