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instance method

IO#flush

flush → self

VALUE
rb_io_flush(VALUE io)
{
    return rb_io_flush_raw(io, 1);
}

Flushes data buffered in self to the operating system (but does not necessarily flush data buffered in the operating system):

Example

$stdout.print 'no newline' # Not necessarily flushed.
$stdout.flush              # Flushed.

See also #fileno #fsync #fdatasync #getbyte also in 4.1 · 4.0 · 3.4 · 3.3 · 3.1 · 3.0