ferror

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 >= 1 || _XOPEN_SOURCE || _POSIX_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 non-zero if it is set.  The end-of-file
       indicator can only be cleared by the function clearerr().

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

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

       For non-locking 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.)

CONFORMING TO
       The functions clearerr(), feof(), and ferror() conform to C89 and C99.

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

COLOPHON
       This  page  is  part of release 3.23 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.



                                  2008-08-29                         FERROR(3)