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flush - Flush buffered output for a channel
flush channelId _________________________________________________________________
Flushes any output that has been buffered for channelId. ChannelId must be a channel identifier such as returned by a previous open or socket command, and it must have been opened for writing. If the │ channel is in blocking mode the command does not return until all the │ buffered output has been flushed to the channel. If the channel is in │ nonblocking mode, the command may return before all buffered output has │ been flushed; the remainder will be flushed in the background as fast │ as the underlying file or device is able to absorb it.
open(n), socket(n)
blocking, buffer, channel, flush, nonblocking, output