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/*

 * Copyright (c) 1990 The Regents of the University of California.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms are permitted

 * provided that the above copyright notice and this paragraph are

 * duplicated in all such forms and that any documentation,

 * advertising materials, and other materials related to such

 * distribution and use acknowledge that the software was developed

 * by the University of California, Berkeley.  The name of the

 * University may not be used to endorse or promote products derived

 * from this software without specific prior written permission.

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

 */

/*

FUNCTION

<<getc>>---read a character (macro)

INDEX

        getc

INDEX

        _getc_r

ANSI_SYNOPSIS

        #include <stdio.h>

        int getc(FILE *<[fp]>);

        #include <stdio.h>

        int _getc_r(struct _reent *<[ptr]>, FILE *<[fp]>);

TRAD_SYNOPSIS

        #include <stdio.h>

        int getc(<[fp]>)

        FILE *<[fp]>;

        #include <stdio.h>

        int _getc_r(<[ptr]>, <[fp]>)

        struct _reent *<[ptr]>;

        FILE *<[fp]>;

DESCRIPTION

<<getc>> is a macro, defined in <<stdio.h>>.  You can use <<getc>>

to get the next single character from the file or stream

identified by <[fp]>.  As a side effect, <<getc>> advances the file's

current position indicator.

For a subroutine version of this macro, see <<fgetc>>.

The <<_getc_r>> function is simply the reentrant version of <<getc>>

which passes an additional reentrancy structure pointer argument: <[ptr]>.

RETURNS

The next character (read as an <<unsigned char>>, and cast to

<<int>>), unless there is no more data, or the host system reports a

read error; in either of these situations, <<getc>> returns <<EOF>>.

You can distinguish the two situations that cause an <<EOF>> result by

using the <<ferror>> and <<feof>> functions.

PORTABILITY

ANSI C requires <<getc>>; it suggests, but does not require, that

<<getc>> be implemented as a macro.  The standard explicitly permits

macro implementations of <<getc>> to use the argument more than once;

therefore, in a portable program, you should not use an expression

with side effects as the <<getc>> argument.

Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,

<<lseek>>, <<read>>, <<sbrk>>, <<write>>.

*/

#if defined(LIBC_SCCS) && !defined(lint)

static char sccsid[] = "%W% (Berkeley) %G%";

#endif /* LIBC_SCCS and not lint */

#include <_ansi.h>

#include <stdio.h>

#include "local.h"

/*

 * A subroutine version of the macro getc.

 */

#undef getc

int

_DEFUN(_getc_r, (ptr, fp),

       struct _reent *ptr _AND

       register FILE *fp)

{

  int result;

  CHECK_INIT (ptr, fp);

  __sfp_lock_acquire ();

  _flockfile (fp);

  result = __sgetc_r (ptr, fp);

  _funlockfile (fp);

  __sfp_lock_release ();

  return result;

}

#ifndef _REENT_ONLY

int

_DEFUN(getc, (fp),

       register FILE *fp)

{

  int result;

  CHECK_INIT (_REENT, fp);

  __sfp_lock_acquire ();

  _flockfile (fp);

  result = __sgetc_r (_REENT, fp);

  _funlockfile (fp);

  __sfp_lock_release ();

  return result;

}

#endif /* !_REENT_ONLY */