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FERROR(3)		    Library Functions Manual		     FERROR(3)

NAME
       clearerr,     clearerr_unlocked,	    feof,    feof_unlocked,    ferror,
       ferror_unlocked,	fileno,	fileno_unlocked	-- check and reset stream sta-
       tus

LIBRARY
       Standard	C Library (libc, -lc)

SYNOPSIS
       #include	<stdio.h>

       void
       clearerr(FILE *stream);

       void
       clearerr_unlocked(FILE *stream);

       int
       feof(FILE *stream);

       int
       feof_unlocked(FILE *stream);

       int
       ferror(FILE *stream);

       int
       ferror_unlocked(FILE *stream);

       int
       fileno(FILE *stream);

       int
       fileno_unlocked(FILE *stream);

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  may  be  cleared  by	explicitly calling clearerr(), or as a
       side-effect of other operations,	e.g. fseek().

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

       The  function fileno() examines the argument stream and returns its in-
       teger descriptor.

       The  clearerr_unlocked(),   feof_unlocked(),   ferror_unlocked(),   and
       fileno_unlocked()  functions  are  equivalent  to  clearerr(),  feof(),
       ferror(), and fileno() respectively, except that	the caller is  respon-
       sible  for  locking  the	 stream	with flockfile(3) before calling them.
       These functions may be used to avoid the	overhead of locking the	stream
       and to prevent races when multiple threads are operating	 on  the  same
       stream.

ERRORS
       These  functions	 should	 not fail and do not set the external variable
       errno.

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

STANDARDS
       The functions clearerr(),  feof(),  and	ferror()  conform  to  ISO/IEC
       9899:1990 ("ISO C90").

HISTORY
       The functions clearerr(), feof(), ferror(), and fileno()	first appeared
       in Version 7 AT&T UNIX.

FreeBSD	13.2			 April 2, 2022			     FERROR(3)
NAME | LIBRARY | SYNOPSIS | DESCRIPTION | ERRORS | SEE ALSO | STANDARDS | HISTORY

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