FFLUSH(3)                 OpenBSD Programmer's Manual                FFLUSH(3)

NAME
     fflush, fpurge - flush a stream



SYNOPSIS
     #include <stdio.h>

     int
     fflush(FILE *stream);

     int
     fpurge(FILE *stream);

DESCRIPTION
     The function fflush() forces a write of all buffered data for the given
     output or update stream via the stream's underlying write function.  The
     open status of the stream is unaffected.

     If the stream argument is NULL, fflush() flushes all open output streams.

     The function fpurge() erases any input or output buffered in the given
     stream. For output streams this discards any unwritten output.  For input
     streams this discards any input read from the underlying object but not
     yet obtained via getc(3);  this includes any text pushed back via ungetc.


RETURN VALUES
     Upon successful completion 0 is returned.  Otherwise, EOF is returned and
     the global variable errno is set to indicate the error.

ERRORS
     [EBADF]       stream is not an open stream, or, in the case of fflush(),
                   not a stream open for writing.

     The function fflush() may also fail and set errno for any of the errors
     specified for the routine write(2).

SEE ALSO
     write(2),  fclose(3),  fopen(3),  setbuf(3)

STANDARDS
     The fflush() function conforms to ANSI X3.159-1989 (``ANSI C'').

OpenBSD 2.6                      June 4, 1993                                1