Editing Bitstream (section)

==Flow control==
Often the contents of a bytestream are dynamically created, such as the data from the keyboard and other peripherals (/dev/tty), data from the [[pseudorandom number generator]] ([[/dev/urandom]]), etc.

In those cases, when the destination of a bytestream (the consumer) uses bytes faster than they can be generated, the system uses [[process synchronization]] to make the destination wait until the next byte is available.

When bytes are generated faster than the destination can use them and the producer is a software algorithm, the system pauses it with the same process synchronization techniques. When the producer supports [[flow control (data)|flow control]], the system only sends the ''ready'' signal when the consumer is ready for the next byte. When the producer can not be paused—a keyboard or some hardware that does not support flow control—the system typically attempts to temporarily store the data until the consumer is ready for it, typically using a [[queue (abstract data type)|queue]]. Often the receiver can empty the buffer before it gets completely full. A producer that continues to produce data faster than it can be consumed, even after the buffer is full, leads to unwanted [[buffer overflow]], [[packet loss]], [[network congestion]], and [[denial of service]].