80 lines
2.5 KiB
C
80 lines
2.5 KiB
C
/*
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* Copyright (c) 1990 The Regents of the University of California.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms are permitted
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* provided that the above copyright notice and this paragraph are
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* duplicated in all such forms and that any documentation,
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* advertising materials, and other materials related to such
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* distribution and use acknowledge that the software was developed
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* by the University of California, Berkeley. The name of the
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* University may not be used to endorse or promote products derived
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* from this software without specific prior written permission.
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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*/
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/*
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FUNCTION
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<<setbuf>>---specify full buffering for a file or stream
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INDEX
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setbuf
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ANSI_SYNOPSIS
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#include <stdio.h>
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void setbuf(FILE *<[fp]>, char *<[buf]>);
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TRAD_SYNOPSIS
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#include <stdio.h>
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void setbuf(<[fp]>, <[buf]>)
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FILE *<[fp]>;
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char *<[buf]>;
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DESCRIPTION
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<<setbuf>> specifies that output to the file or stream identified by <[fp]>
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should be fully buffered. All output for this file will go to a
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buffer (of size <<BUFSIZ>>, specified in `<<stdio.h>>'). Output will
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be passed on to the host system only when the buffer is full, or when
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an input operation intervenes.
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You may, if you wish, supply your own buffer by passing a pointer to
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it as the argument <[buf]>. It must have size <<BUFSIZ>>. You can
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also use <<NULL>> as the value of <[buf]>, to signal that the
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<<setbuf>> function is to allocate the buffer.
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WARNINGS
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You may only use <<setbuf>> before performing any file operation other
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than opening the file.
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If you supply a non-null <[buf]>, you must ensure that the associated
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storage continues to be available until you close the stream
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identified by <[fp]>.
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RETURNS
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<<setbuf>> does not return a result.
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PORTABILITY
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Both ANSI C and the System V Interface Definition (Issue 2) require
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<<setbuf>>. However, they differ on the meaning of a <<NULL>> buffer
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pointer: the SVID issue 2 specification says that a <<NULL>> buffer
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pointer requests unbuffered output. For maximum portability, avoid
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<<NULL>> buffer pointers.
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Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
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<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
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*/
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#include <_ansi.h>
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#include <stdio.h>
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#include "local.h"
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_VOID
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_DEFUN(setbuf, (fp, buf),
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FILE *__restrict fp _AND
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char *__restrict buf)
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{
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_CAST_VOID setvbuf (fp, buf, buf ? _IOFBF : _IONBF, BUFSIZ);
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}
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