NAME
getc - get a byte from a stream
SYNOPSIS
#include <stdio.h>
int getc(FILE *stream);
DESCRIPTION
The getc() function shall be equivalent to fgetc() , except that if it
is implemented as a macro it may evaluate stream more than once, so the
argument should never be an expression with side effects.
RETURN VALUE
Refer to fgetc() .
ERRORS
Refer to fgetc() .
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
If the integer value returned by getc() is stored into a variable of
type char and then compared against the integer constant EOF, the
comparison may never succeed, because sign-extension of a variable of
type char on widening to integer is implementation-defined.
Since it may be implemented as a macro, getc() may treat incorrectly a
stream argument with side effects. In particular, getc(*f++) does not
necessarily work as expected. Therefore, use of this function should
be preceded by "#undef getc" in such situations; fgetc() could also be
used.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
fgetc() , the Base Definitions volume of IEEE Std 1003.1-2001,
<stdio.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online
at http://www.opengroup.org/unix/online.html .