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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 .