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To: questions@freebsd.org
cc: ivan@cyclades.com
Subject: ENOENT on read? (Problem with tip)
Date: Wed, 30 Jul 1997 13:20:37 -0400
From: Brian McGovern <bmcgover@cisco.com>
Sender: owner-freebsd-questions@freebsd.org
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I'm having problems with tip connecting to a serial port. I've tracked the
point of failure to the line just after the printf("Point 1\n"); below. I've 
now reached the point where "I just don't get it" (tm).

I've found, from hunt.c, that its trying to open /dev/cuacA00, which is the
correct device, so the "No such file or directory" description in 
/usr/include/sys/errno.h makes little sense. Also, the descriptor FD is
usually either 3 or 4, so its not that its a bad descriptor from the
open, either. Lastly, I don't see any calls to fnctl to set the socket
non-blocking (or in the open for that matter), so the read should
block until there is data.

Anyhow, any sugguestions are welcome.
	-Brian


for (omask = 0;; sigsetmask(omask)) 
  {
    cnt = read(FD, buf, BUFSIZ);
    if (cnt <= 0)
      {
        /* lost carrier */
        if (cnt < 0 && errno == EIO)
	  {
            sigblock(sigmask(SIGTERM));
            intTERM();
            /*NOTREACHED*/
          }
        else
	  if (cnt == 0 && errno == ENOENT)
	    {
              printf("Point 1\n");
	      if (getppid() != 1)
	        kill(getppid(),SIGUSR1);
	      sigblock(sigmask(SIGTERM));
	      intTERM();
	      /*NOTREACHED*/
	    }
	  else
	    if (cnt < 0)
	      {
                printf("Point 2\n");
		if (getppid() != 1)
	  	  kill(getppid(),SIGUSR1);
		sigblock(sigmask(SIGTERM));
		intTERM();
		/*NOTREACHED*/
              }
	    continue;
	}