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FFLUSH(3)                BSD Library Functions Manual                FFLUSH(3)

NAME
     fflush, fpurge -- flush a stream

LIBRARY
     Standard C Library (libc, -lc)

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(3).

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]            The stream argument 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 ISO/IEC 9899:1990 (``ISO C90'').

BSD                              June 4, 1993                              BSD