/*
|
/*
|
* Copyright (c) 1990 The Regents of the University of California.
|
* Copyright (c) 1990 The Regents of the University of California.
|
* All rights reserved.
|
* All rights reserved.
|
*
|
*
|
* Redistribution and use in source and binary forms are permitted
|
* Redistribution and use in source and binary forms are permitted
|
* provided that the above copyright notice and this paragraph are
|
* provided that the above copyright notice and this paragraph are
|
* duplicated in all such forms and that any documentation,
|
* duplicated in all such forms and that any documentation,
|
* advertising materials, and other materials related to such
|
* advertising materials, and other materials related to such
|
* distribution and use acknowledge that the software was developed
|
* distribution and use acknowledge that the software was developed
|
* by the University of California, Berkeley. The name of the
|
* by the University of California, Berkeley. The name of the
|
* University may not be used to endorse or promote products derived
|
* University may not be used to endorse or promote products derived
|
* from this software without specific prior written permission.
|
* from this software without specific prior written permission.
|
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
|
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
|
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
|
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
*/
|
*/
|
|
|
/*
|
/*
|
FUNCTION
|
FUNCTION
|
<<freopen>>---open a file using an existing file descriptor
|
<<freopen>>---open a file using an existing file descriptor
|
|
|
INDEX
|
INDEX
|
freopen
|
freopen
|
|
|
ANSI_SYNOPSIS
|
ANSI_SYNOPSIS
|
#include <stdio.h>
|
#include <stdio.h>
|
FILE *freopen(const char *<[file]>, const char *<[mode]>,
|
FILE *freopen(const char *<[file]>, const char *<[mode]>,
|
FILE *<[fp]>);
|
FILE *<[fp]>);
|
|
|
TRAD_SYNOPSIS
|
TRAD_SYNOPSIS
|
#include <stdio.h>
|
#include <stdio.h>
|
FILE *freopen(<[file]>, <[mode]>, <[fp]>)
|
FILE *freopen(<[file]>, <[mode]>, <[fp]>)
|
char *<[file]>;
|
char *<[file]>;
|
char *<[mode]>;
|
char *<[mode]>;
|
FILE *<[fp]>;
|
FILE *<[fp]>;
|
|
|
DESCRIPTION
|
DESCRIPTION
|
Use this variant of <<fopen>> if you wish to specify a particular file
|
Use this variant of <<fopen>> if you wish to specify a particular file
|
descriptor <[fp]> (notably <<stdin>>, <<stdout>>, or <<stderr>>) for
|
descriptor <[fp]> (notably <<stdin>>, <<stdout>>, or <<stderr>>) for
|
the file.
|
the file.
|
|
|
If <[fp]> was associated with another file or stream, <<freopen>>
|
If <[fp]> was associated with another file or stream, <<freopen>>
|
closes that other file or stream (but ignores any errors while closing
|
closes that other file or stream (but ignores any errors while closing
|
it).
|
it).
|
|
|
<[file]> and <[mode]> are used just as in <<fopen>>.
|
<[file]> and <[mode]> are used just as in <<fopen>>.
|
|
|
RETURNS
|
RETURNS
|
If successful, the result is the same as the argument <[fp]>. If the
|
If successful, the result is the same as the argument <[fp]>. If the
|
file cannot be opened as specified, the result is <<NULL>>.
|
file cannot be opened as specified, the result is <<NULL>>.
|
|
|
PORTABILITY
|
PORTABILITY
|
ANSI C requires <<freopen>>.
|
ANSI C requires <<freopen>>.
|
|
|
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
|
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
|
<<lseek>>, <<open>>, <<read>>, <<sbrk>>, <<write>>.
|
<<lseek>>, <<open>>, <<read>>, <<sbrk>>, <<write>>.
|
*/
|
*/
|
|
|
#include <time.h>
|
#include <time.h>
|
#include <stdio.h>
|
#include <stdio.h>
|
#include <fcntl.h>
|
#include <fcntl.h>
|
#include <stdlib.h>
|
#include <stdlib.h>
|
#include "local.h"
|
#include "local.h"
|
|
|
/*
|
/*
|
* Re-direct an existing, open (probably) file to some other file.
|
* Re-direct an existing, open (probably) file to some other file.
|
*/
|
*/
|
|
|
FILE *
|
FILE *
|
_DEFUN (freopen, (file, mode, fp),
|
_DEFUN (freopen, (file, mode, fp),
|
_CONST char *file _AND
|
_CONST char *file _AND
|
_CONST char *mode _AND
|
_CONST char *mode _AND
|
register FILE *fp)
|
register FILE *fp)
|
{
|
{
|
register int f;
|
register int f;
|
int flags, oflags, e;
|
int flags, oflags, e;
|
struct _reent *ptr;
|
struct _reent *ptr;
|
|
|
CHECK_INIT (fp);
|
CHECK_INIT (fp);
|
ptr = fp->_data;
|
ptr = fp->_data;
|
|
|
if ((flags = __sflags (ptr, mode, &oflags)) == 0)
|
if ((flags = __sflags (ptr, mode, &oflags)) == 0)
|
{
|
{
|
(void) fclose (fp);
|
(void) fclose (fp);
|
return NULL;
|
return NULL;
|
}
|
}
|
|
|
/*
|
/*
|
* Remember whether the stream was open to begin with, and
|
* Remember whether the stream was open to begin with, and
|
* which file descriptor (if any) was associated with it.
|
* which file descriptor (if any) was associated with it.
|
* If it was attached to a descriptor, defer closing it,
|
* If it was attached to a descriptor, defer closing it,
|
* so that, e.g., freopen("/dev/stdin", "r", stdin) works.
|
* so that, e.g., freopen("/dev/stdin", "r", stdin) works.
|
* This is unnecessary if it was not a Unix file.
|
* This is unnecessary if it was not a Unix file.
|
*/
|
*/
|
|
|
if (fp->_flags == 0)
|
if (fp->_flags == 0)
|
fp->_flags = __SEOF; /* hold on to it */
|
fp->_flags = __SEOF; /* hold on to it */
|
else
|
else
|
{
|
{
|
if (fp->_flags & __SWR)
|
if (fp->_flags & __SWR)
|
(void) fflush (fp);
|
(void) fflush (fp);
|
/* if close is NULL, closing is a no-op, hence pointless */
|
/* if close is NULL, closing is a no-op, hence pointless */
|
if (fp->_close != NULL)
|
if (fp->_close != NULL)
|
(void) (*fp->_close) (fp->_cookie);
|
(void) (*fp->_close) (fp->_cookie);
|
}
|
}
|
|
|
/*
|
/*
|
* Now get a new descriptor to refer to the new file.
|
* Now get a new descriptor to refer to the new file.
|
*/
|
*/
|
|
|
f = _open_r (ptr, (char *) file, oflags, 0666);
|
f = _open_r (ptr, (char *) file, oflags, 0666);
|
e = ptr->_errno;
|
e = ptr->_errno;
|
|
|
/*
|
/*
|
* Finish closing fp. Even if the open succeeded above,
|
* Finish closing fp. Even if the open succeeded above,
|
* we cannot keep fp->_base: it may be the wrong size.
|
* we cannot keep fp->_base: it may be the wrong size.
|
* This loses the effect of any setbuffer calls,
|
* This loses the effect of any setbuffer calls,
|
* but stdio has always done this before.
|
* but stdio has always done this before.
|
*/
|
*/
|
|
|
if (fp->_flags & __SMBF)
|
if (fp->_flags & __SMBF)
|
_free_r (ptr, (char *) fp->_bf._base);
|
_free_r (ptr, (char *) fp->_bf._base);
|
fp->_w = 0;
|
fp->_w = 0;
|
fp->_r = 0;
|
fp->_r = 0;
|
fp->_p = NULL;
|
fp->_p = NULL;
|
fp->_bf._base = NULL;
|
fp->_bf._base = NULL;
|
fp->_bf._size = 0;
|
fp->_bf._size = 0;
|
fp->_lbfsize = 0;
|
fp->_lbfsize = 0;
|
if (HASUB (fp))
|
if (HASUB (fp))
|
FREEUB (fp);
|
FREEUB (fp);
|
fp->_ub._size = 0;
|
fp->_ub._size = 0;
|
if (HASLB (fp))
|
if (HASLB (fp))
|
FREELB (fp);
|
FREELB (fp);
|
fp->_lb._size = 0;
|
fp->_lb._size = 0;
|
|
|
if (f < 0)
|
if (f < 0)
|
{ /* did not get it after all */
|
{ /* did not get it after all */
|
fp->_flags = 0; /* set it free */
|
fp->_flags = 0; /* set it free */
|
ptr->_errno = e; /* restore in case _close clobbered */
|
ptr->_errno = e; /* restore in case _close clobbered */
|
return NULL;
|
return NULL;
|
}
|
}
|
|
|
fp->_flags = flags;
|
fp->_flags = flags;
|
fp->_file = f;
|
fp->_file = f;
|
fp->_cookie = (_PTR) fp;
|
fp->_cookie = (_PTR) fp;
|
fp->_read = __sread;
|
fp->_read = __sread;
|
fp->_write = __swrite;
|
fp->_write = __swrite;
|
fp->_seek = __sseek;
|
fp->_seek = __sseek;
|
fp->_close = __sclose;
|
fp->_close = __sclose;
|
|
|
#ifdef __SCLE
|
#ifdef __SCLE
|
if (__stextmode(fp->_file))
|
if (__stextmode(fp->_file))
|
fp->_flags |= __SCLE;
|
fp->_flags |= __SCLE;
|
#endif
|
#endif
|
|
|
return fp;
|
return fp;
|
}
|
}
|
|
|
