Files
gnu-coreutils/lib/xgethostname.c
T
Jim Meyering 4d091498a4 Thu Oct 31 19:32:32 1996 Miles Bader <miles@gnu.ai.mit.edu>
[ENAMETOOLONG] (xgethostname): If gethostname
returns an error other than buffer overflow, exit with an error
message instead of allocating infinite amounts of space.
[!EXIT_FAILURE] (EXIT_FAILURE): New macro.
<errno.h>: New include.
[!errno] (errno): New declaration.
1996-11-05 04:38:41 +00:00

71 lines
1.7 KiB
C

/* xgethostname.c -- return current hostname with unlimited length
Copyright (C) 1992, 1996 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* Written by Jim Meyering, meyering@comco.com */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <sys/types.h>
#include <errno.h>
#ifndef errno
extern int errno;
#endif
#include "error.h"
#ifndef EXIT_FAILURE
# define EXIT_FAILURE 1
#endif
int gethostname ();
char *xmalloc ();
char *xrealloc ();
#ifndef INITIAL_HOSTNAME_LENGTH
# define INITIAL_HOSTNAME_LENGTH 33
#endif
char *
xgethostname ()
{
char *hostname;
size_t size;
int err;
size = INITIAL_HOSTNAME_LENGTH;
hostname = xmalloc (size);
while (1)
{
errno = 0;
hostname[size - 1] = '\0';
err = gethostname (hostname, size);
if (err == 0 && hostname[size - 1] == '\0')
break;
#ifdef ENAMETOOLONG
else if (err != 0 && errno != ENAMETOOLONG && errno != 0)
error (EXIT_FAILURE, errno, "gethostname");
#endif
size *= 2;
hostname = xrealloc (hostname, size);
}
return hostname;
}