stat/fstat incompatibility w/ unix sockets

[Corinna Vinschen]

On Thu, Feb 20, 2003 at 06:47:39PM -0500, Paul Swartz wrote:
> On 20 Feb 2003 at 22:40, Corinna Vinschen wrote:
> > As you can see, there's also nothing which would help you in using the
> > result to identify the sockets as being the same.  Even the timestamps
> > aren't identical.
> 
> No one field can say it's the same file.  All of them together, or a 
> sufficiently large number of them, does.

Nope.  How should they?  The really interesting fields are not identical
as e. g. st_dev, st_ino, st_mode, st_ctime.  Anyway, that's not a Cygwin
issue anymore.

> Even if it isn't completely portable, at the very least, things like the 
> uid/gid definatly shouldn't change.  The ctime/mtime probably shouldn't 
> either, I'm less sure about atime.  I don't have a copy of POSIX, does that 
> say anything about the stat/fstat semantics?

SUSv3: http://www.opengroup.org/

Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Developer                                mailto:cygwin@cygwin.com
Red Hat, Inc.
-------------- next part --------------
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <sys/un.h>
#include <unistd.h>

int
main (int argc, char **argv)
{
  int fd;
  struct sockaddr_un addr;
  socklen_t addrlen;
  char buf[100];
  struct stat st;

  /* creating test unix domain socket pipe */
  fd = socket(AF_UNIX, SOCK_DGRAM, 0);
  /* SOCK_DGRAM require this to bind */
  bzero((char *)&addr, sizeof(addr));
  /* fill in addr structire */
  addr.sun_family = AF_UNIX;
  strcpy(addr.sun_path, "pipe.101");
  addrlen = sizeof(addr.sun_family) + strlen(addr.sun_path) + 1;
  /* unlink old socket file */
  unlink(addr.sun_path);
  /* bind socket to special file named pipe.100 in current directory */
  bind(fd, (struct sockaddr *)&addr, addrlen);

  printf ("STAT      : \"%s\"\n", addr.sun_path);
  if (!stat (addr.sun_path, &st))
    {
      printf ("st_dev    : 0x%x\n",  st.st_dev);
      printf ("st_ino    : %lu\n",  st.st_ino);
      printf ("st_mode   : 0%o\n",  st.st_mode);
      printf ("st_nlink  : %d\n",  st.st_nlink);
      printf ("st_uid    : %d\n",  st.st_uid);
      printf ("st_gid    : %d\n",  st.st_gid);
      printf ("st_rdev   : 0x%x\n",  st.st_rdev);
      printf ("st_size   : %ld\n",  st.st_size);
      printf ("st_blksize: %ld\n",  st.st_blksize);
      printf ("st_blocks : %ld\n",  st.st_blocks);
      printf ("st_ctime : %ld\n",  st.st_ctime);
      printf ("st_mtime : %ld\n",  st.st_mtime);
      printf ("st_atime : %ld\n",  st.st_atime);
    }
  printf ("FSTAT     : \"%s\"\n", addr.sun_path);
  if (!fstat (fd, &st))
    {
      printf ("st_dev    : 0x%x\n",  st.st_dev);
      printf ("st_ino    : %lu\n",  st.st_ino);
      printf ("st_mode   : 0%o\n",  st.st_mode);
      printf ("st_nlink  : %d\n",  st.st_nlink);
      printf ("st_uid    : %d\n",  st.st_uid);
      printf ("st_gid    : %d\n",  st.st_gid);
      printf ("st_rdev   : 0x%x\n",  st.st_rdev);
      printf ("st_size   : %ld\n",  st.st_size);
      printf ("st_blksize: %ld\n",  st.st_blksize);
      printf ("st_blocks : %ld\n",  st.st_blocks);
      printf ("st_ctime : %ld\n",  st.st_ctime);
      printf ("st_mtime : %ld\n",  st.st_mtime);
      printf ("st_atime : %ld\n",  st.st_atime);
    }
  return 0;
}

-------------- next part --------------
--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Bug reporting:         http://cygwin.com/bugs.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/