sl@0: /* FFLUSH.C
sl@0:  * 
sl@0:  * Portions Copyright (c) 1990-2006 Nokia Corporation and/or its subsidiary(-ies).
sl@0:  * All rights reserved.
sl@0:  */
sl@0: 
sl@0: /*
sl@0:  * Copyright (c) 1990 The Regents of the University of California.
sl@0:  * All rights reserved.
sl@0:  *
sl@0:  * Redistribution and use in source and binary forms are permitted
sl@0:  * provided that the above copyright notice and this paragraph are
sl@0:  * duplicated in all such forms and that any documentation,
sl@0:  * advertising materials, and other materials related to such
sl@0:  * distribution and use acknowledge that the software was developed
sl@0:  * by the University of California, Berkeley.  The name of the
sl@0:  * University may not be used to endorse or promote products derived
sl@0:  * from this software without specific prior written permission.
sl@0:  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
sl@0:  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
sl@0:  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
sl@0:  */
sl@0: 
sl@0: /*
sl@0: FUNCTION
sl@0: <<fflush>>---flush buffered file output
sl@0: 
sl@0: INDEX
sl@0: 	fflush
sl@0: 
sl@0: ANSI_SYNOPSIS
sl@0: 	#include <stdio.h>
sl@0: 	int fflush(FILE *<[fp]>);
sl@0: 
sl@0: TRAD_SYNOPSIS
sl@0: 	#include <stdio.h>
sl@0: 	int fflush(<[fp]>)
sl@0: 	FILE *<[fp]>;
sl@0: 
sl@0: DESCRIPTION
sl@0: The <<stdio>> output functions can buffer output before delivering it
sl@0: to the host system, in order to minimize the overhead of system calls.
sl@0: 
sl@0: Use <<fflush>> to deliver any such pending output (for the file
sl@0: or stream identified by <[fp]>) to the host system.
sl@0: 
sl@0: If <[fp]> is <<NULL>>, <<fflush>> delivers pending output from all
sl@0: open files.
sl@0: 
sl@0: RETURNS
sl@0: <<fflush>> returns <<0>> unless it encounters a write error; in that
sl@0: situation, it returns <<EOF>>.
sl@0: 
sl@0: PORTABILITY
sl@0: ANSI C requires <<fflush>>.
sl@0: 
sl@0: No supporting OS subroutines are required.
sl@0: */
sl@0: 
sl@0: #include <stdio.h>
sl@0: #include "LOCAL.H"
sl@0: 
sl@0: /**
sl@0: Flush a stream. If the given stream has been opened for writing operations
sl@0: the output buffer is phisically written to the file. If the stream was open
sl@0: for reading operations the content of the input buffer is cleared. The stream
sl@0: remains open after this call.
sl@0: 
sl@0: @param fp pointer to an open file.
sl@0: 
sl@0: @return On Success, a 0 value indicates success.
sl@0: 		On Failure, EOF is returned and errno may be set.
sl@0: */
sl@0: EXPORT_C int
sl@0: fflush (FILE * fp)
sl@0: {
sl@0:   register unsigned char *p;
sl@0:   register int n, t;
sl@0: 
sl@0:   if (fp == NULL)
sl@0:   	{
sl@0:     struct _reent *r = _REENT2;
sl@0:     if (!r)
sl@0: 	  return EOF; // Memory for library globals is not allocated (errno not set).
sl@0:     return _fwalk (r, fflush);
sl@0:   	}
sl@0:   CHECK_INIT (fp);
sl@0: 
sl@0:   t = fp->_flags;
sl@0:   if ((t & __SWR) == 0 || (p = fp->_bf._base) == NULL)
sl@0:     return 0;
sl@0:   n = fp->_p - p;		/* write this much */
sl@0: 
sl@0:   /*
sl@0:    * Set these immediately to avoid problems with longjmp
sl@0:    * and to allow exchange buffering (via setvbuf) in user
sl@0:    * write function.
sl@0:    */
sl@0:   fp->_p = p;
sl@0:   fp->_w = t & (__SLBF | __SNBF) ? 0 : fp->_bf._size;
sl@0: 
sl@0:   while (n > 0)
sl@0:     {
sl@0:       t = (*fp->_write) (fp->_cookie, (char *) p, n);
sl@0:       if (t <= 0)
sl@0: 	{
sl@0: 	  fp->_flags |= __SERR;
sl@0: 	  return EOF;
sl@0: 	}
sl@0:       p += t;
sl@0:       n -= t;
sl@0:     }
sl@0:   return 0;
sl@0: }