genericopenlibs/cstdlib/LSTDIO/GETC.C
author Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
Mon, 04 Oct 2010 02:56:42 +0300
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/* GETC.C
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 * 
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 * Portions Copyright (c) 1990-1999 Nokia Corporation and/or its subsidiary(-ies).
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 * All rights reserved.
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 */
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/*
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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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<<getc>>---read a character (macro)
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INDEX
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	getc
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ANSI_SYNOPSIS
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	#include <stdio.h>
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	int getc(FILE *<[fp]>);
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TRAD_SYNOPSIS
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	#include <stdio.h>
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	int getc(<[fp]>)
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	FILE *<[fp]>;
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DESCRIPTION
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<<getc>> is a macro, defined in <<stdio.h>>.  You can use <<getc>>
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to get the next single character from the file or stream
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identified by <[fp]>.  As a side effect, <<getc>> advances the file's
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current position indicator.
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For a subroutine version of this macro, see <<fgetc>>.
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RETURNS
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The next character (read as an <<unsigned char>>, and cast to
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<<int>>), unless there is no more data, or the host system reports a
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read error; in either of these situations, <<getc>> returns <<EOF>>.
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You can distinguish the two situations that cause an <<EOF>> result by
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using the <<ferror>> and <<feof>> functions.
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PORTABILITY
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ANSI C requires <<getc>>; it suggests, but does not require, that
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<<getc>> be implemented as a macro.  The standard explicitly permits
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macro implementations of <<getc>> to use the argument more than once;
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therefore, in a portable program, you should not use an expression
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with side effects as the <<getc>> argument.
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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 <stdio.h>
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#include "LOCAL.H"
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/*
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 * A subroutine version of the macro getc.
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 */
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#undef getc
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/**
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Get the next character.
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Returns the next character of the stream and increases the file pointer
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to point to the next character.
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@return The character read is returned as an int value.
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If the End Of File has been reached or there has been an error reading, 
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the function returns EOF.
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@param fp pointer to an open file.
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*/
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EXPORT_C int
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getc (register FILE *fp)
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{
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  /* CHECK_INIT is called (eventually) by __srefill.  */
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  return __sgetc (fp);
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}