glibc/stdio/newstream.c
1995-02-18 01:27:10 +00:00

55 lines
1.6 KiB
C

/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <ansidecl.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
/* Return a new, zeroed, stream.
You must set its cookie and io_mode.
The first operation will give it a buffer unless you do.
It will also give it the default functions unless you set the `seen' flag.
Returns NULL if a stream can't be created. */
FILE *
DEFUN_VOID(__newstream)
{
register FILE *stream;
stream = __stdio_head;
while (__validfp (stream))
stream = stream->__next;
if (stream == NULL)
{
/* None to reuse. */
stream = (FILE *) malloc (sizeof (FILE));
if (stream == NULL)
return NULL;
stream->__next = __stdio_head;
__stdio_head = stream;
}
__invalidate (stream);
stream->__magic = _IOMAGIC;
stream->__offset = (fpos_t) -1;
stream->__target = (fpos_t) -1;
return stream;
}