GETC(3)

NAME
getc, _getc_r - read a character (macro)

SYNOPSIS

#include <stdio.h>

int getc(FILE *fp);

#include <stdio.h>

int _getc_r(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.

AUTHORS

Steve Chamberlain
    Author.

Roland Pesch
    Author.

Red Hat Support

Jeff Johnston
    Author.

COPYRIGHT

This file documents the ANSI C library.

Copyright (C) 1992, 1993, 1994-2014 Red Hat, Inc.

libc includes software developed by the University of California, Berkeley and its contributors.

libc includes software developed by Martin Jackson, Graham Haley and Steve Chamberlain of Tadpole Technology and released to Cygnus.

libc uses floating-point conversion software developed at AT&T, which includes this copyright information:

The author of this software is David M. Gay.

Copyright (c) 1991 by AT&T.

Permission to use, copy, modify, and distribute this software for any purpose without fee is hereby granted, provided that this entire notice is included in all copies of any software which is or includes a copy or modification of this software and in all copies of the supporting documentation for such software.

THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED WARRANTY. IN PARTICULAR, NEITHER THE AUTHOR NOR AT&T MAKES ANY REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.

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Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, subject to the terms of the GNU General Public License, which includes the provision that the entire resulting derived work is distributed under the terms of a permission notice identical to this one.

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