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FGETC(P)			    POSIX Programmer's Manual				 FGETC(P)

NAME
       fgetc - get a byte from a stream

SYNOPSIS
       #include <stdio.h>

       int fgetc(FILE *stream);

DESCRIPTION
       If  the	end-of-file  indicator for the input stream pointed to by stream is not set and a
       next byte is present, the fgetc() function shall obtain the next byte as an unsigned  char
       converted  to  an int, from the input stream pointed to by stream, and advance the associ-
       ated file position indicator for the stream (if defined). Since fgetc() operates on bytes,
       reading a character consisting of multiple bytes (or "a multi-byte character") may require
       multiple calls to fgetc().

       The fgetc() function may mark the st_atime field of the file associated	with  stream  for
       update. The st_atime field shall be marked for update by the first successful execution of
       fgetc(), fgets(), fgetwc(), fgetws(), fread(), fscanf(),  getc(),  getchar(),  gets(),  or
       scanf()	using  stream  that  returns  data  not  supplied  by a prior call to ungetc() or
       ungetwc().

RETURN VALUE
       Upon successful completion, fgetc() shall return the  next  byte  from  the  input  stream
       pointed to by stream. If the end-of-file indicator for the stream is set, or if the stream
       is at end-of-file, the end-of-file indicator for the stream shall be set and fgetc() shall
       return  EOF.  If  a  read  error  occurs, the error indicator for the stream shall be set,
       fgetc() shall return EOF,    and shall set errno to indicate the error.

ERRORS
       The fgetc() function shall fail if data needs to be read and:

       EAGAIN The O_NONBLOCK flag is set for  the  file  descriptor  underlying  stream  and  the
	      process would be delayed in the fgetc() operation.

       EBADF  The file descriptor underlying stream is not a valid file descriptor open for read-
	      ing.

       EINTR  The read operation was terminated due to the receipt of a signal, and no	data  was
	      transferred.

       EIO    A  physical I/O error has occurred, or the process is in a background process group
	      attempting to read from its controlling terminal, and either the process is  ignor-
	      ing or blocking the SIGTTIN signal or the process group is orphaned. This error may
	      also be generated for implementation-defined reasons.

       EOVERFLOW
	      The file is a regular file and an attempt was made to read at or beyond the  offset
	      maximum associated with the corresponding stream.

       The fgetc() function may fail if:

       ENOMEM Insufficient storage space is available.

       ENXIO  A request was made of a nonexistent device, or the request was outside the capabil-
	      ities of the device.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       If the integer value returned by fgetc() 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.

       The ferror() or feof() functions must be used to distinguish between  an  error	condition
       and an end-of-file condition.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       feof()  ,  ferror()  ,  fopen()	,  getchar()  ,  getc()  , 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 orig-
       inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group			       2003					 FGETC(P)
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