FERROR(3)		   Linux Programmer's Manual		     FERROR(3)



NAME
       clearerr, feof, ferror, fileno - check and reset stream status

SYNOPSIS
       #include <stdio.h>

       void clearerr(FILE *stream);

       int feof(FILE *stream);

       int ferror(FILE *stream);

       int fileno(FILE *stream);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       fileno(): _POSIX_C_SOURCE

DESCRIPTION
       The function clearerr() clears the end-of-file and error indicators for
       the stream pointed to by stream.

       The function feof() tests the  end-of-file  indicator  for  the	stream
       pointed	to by stream, returning nonzero if it is set.  The end-of-file
       indicator can be cleared only by the function clearerr().

       The function ferror() tests the error indicator for the stream  pointed
       to  by stream, returning nonzero if it is set.  The error indicator can
       be reset only by the clearerr() function.

       The function fileno() examines the  argument  stream  and  returns  its
       integer file descriptor.

       For nonlocking counterparts, see unlocked_stdio(3).

ERRORS
       These  functions	 should	 not fail and do not set the external variable
       errno.  (However, in case fileno() detects that its argument is	not  a
       valid stream, it must return -1 and set errno to EBADF.)

ATTRIBUTES
       For   an	  explanation	of   the  terms	 used  in  this	 section,  see
       attributes(7).

       +--------------------+---------------+---------+
       |Interface	    | Attribute	    | Value   |
       +--------------------+---------------+---------+
       |clearerr(), feof(), | Thread safety | MT-Safe |
       |ferror(), fileno()  |		    |	      |
       +--------------------+---------------+---------+
CONFORMING TO
       The functions clearerr(), feof(), and ferror()  conform	to  C89,  C99,
       POSIX.1-2001, and POSIX.1-2008.

       The function fileno() conforms to POSIX.1-2001 and POSIX.1-2008.

SEE ALSO
       open(2), fdopen(3), stdio(3), unlocked_stdio(3)

COLOPHON
       This  page  is  part of release 4.10 of the Linux man-pages project.  A
       description of the project, information about reporting bugs,  and  the
       latest	  version     of     this    page,    can    be	   found    at
       https://www.kernel.org/doc/man-pages/.



				  2016-03-15			     FERROR(3)