PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of this interface
       may differ (consult the corresponding Linux manual page for details of Linux behavior), or the  interface
       may not be implemented on Linux.

NAME

       getc — get a byte from a stream

SYNOPSIS

       #include <stdio.h>

       int getc(FILE *stream);

DESCRIPTION

       The  functionality  described  on  this  reference  page is aligned with the ISO C standard. Any conflict
       between the requirements described  here  and  the  ISO C  standard  is  unintentional.  This  volume  of
       POSIX.1‐2008 defers to the ISO C standard.

       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 "#undefgetc" in such situations; fgetc() could also be used.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       Section 2.5, Standard I/O Streams, fgetc()

       The Base Definitions volume of POSIX.1‐2008, <stdio.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition,
       Standard  for  Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electrical and Electronics Engineers,  Inc
       and  The  Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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.unix.org/online.html .

       Any  typographical  or formatting errors that appear in this page are most likely to have been introduced
       during  the  conversion  of  the  source  files  to  man  page  format.  To  report  such   errors,   see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                                   2013                                          GETC(3POSIX)