fpurge(3)                                                     fpurge(3)

  fflush()

  NAME

    fflush(), fpurge() - flush a stream

  SYNOPSIS

    #include 

    int fflush (FILE *stream)
    int fpurge (FILE *stream)

  DESCRIPTION

    The function fflush(3) forces a write of all buffered data for the given
    output or update stream through the stream's underlying write function.
    The open status of the stream is unaffected.

    If the stream argument is NULL, fflush(3) flushes all open output streams.

    The function fpurge(3) 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 through getc(3); this includes any text pushed back through
    ungetc(3).

  RETURN VALUES

    Upon successful completion the functions return 0. Otherwise, they return
    EOF and set the global variable errno to indicate the error.

  ERRORS

    [EBADF]
        Stream is not a stream open for writing.

    Fflush(3) can also fail for any of the reasons associated with the
    write(2) function.

  SEE ALSO

    fclose(3)

    fopen(3)

    setbuf(3)

    write(2)

  USAGE NOTES

    All of these functions are thread safe.

    None of these functions are async-signal safe.