1 /*
2  * Copyright (c) 1990 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that the above copyright notice and this paragraph are
7  * duplicated in all such forms and that any documentation,
8  * and/or other materials related to such
9  * distribution and use acknowledge that the software was developed
10  * by the University of California, Berkeley.  The name of the
11  * University may not be used to endorse or promote products derived
12  * from this software without specific prior written permission.
13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16  */
17 /*
18 Modified copy of setbuf.c to support the setbuffer function
19 defined as part of BSD.
20 Modifications by Gareth Pearce, 2001.
21 */
22 
23 /*
24 FUNCTION
25 <<setbuffer>>---specify full buffering for a file or stream with size
26 
27 INDEX
28 	setbuffer
29 
30 SYNOPSIS
31 	#include <stdio.h>
32 	void setbuffer(FILE *<[fp]>, char *<[buf]>, int <[size]>);
33 
34 DESCRIPTION
35 <<setbuffer>> specifies that output to the file or stream identified by
36 <[fp]> should be fully buffered.  All output for this file will go to a
37 buffer (of size <[size]>).  Output will be passed on to the host system
38 only when the buffer is full, or when an input operation intervenes.
39 
40 You may, if you wish, supply your own buffer by passing a pointer to
41 it as the argument <[buf]>.  It must have size <[size]>.  You can
42 also use <<NULL>> as the value of <[buf]>, to signal that the
43 <<setbuffer>> function is to allocate the buffer.
44 
45 WARNINGS
46 You may only use <<setbuffer>> before performing any file operation
47 other than opening the file.
48 
49 If you supply a non-null <[buf]>, you must ensure that the associated
50 storage continues to be available until you close the stream
51 identified by <[fp]>.
52 
53 RETURNS
54 <<setbuffer>> does not return a result.
55 
56 PORTABILITY
57 This function comes from BSD not ANSI or POSIX.
58 
59 Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
60 <<lseek>>, <<read>>, <<sbrk>>, <<write>>.
61 */
62 
63 #define _DEFAULT_SOURCE
64 #include <_ansi.h>
65 #include <stdio.h>
66 #include "local.h"
67 
68 void
setbuffer(FILE * fp,char * buf,int size)69 setbuffer (FILE * fp,
70        char *buf,
71        int size)
72 {
73   (void) setvbuf (fp, buf, buf ? _IOFBF : _IONBF, (size_t) size);
74 }
75