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document updated 13 years ago, on Dec 3, 2010
KSH's coprocesses seem like expect, but inside the shell! Awesome.

O'Reilly's book "Learning the Korn Shell", §8.5 "Coroutines", goes over this a little bit.

Examples of their use

Search strings

When looking at existing scripts, look for these strings, as an indicator of where the specific coroutine code is happening:

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