On 12/5/24 10:19 AM, Dan Cross wrote: > Unix pipelines, on the other hand, tend to be used in a manner that is > strictly linear, without the fan-out and fan-in capabilities described > by Morrison. Of course, nothing prevents one from building a > Morrison-style "network" from Unix processes and pipes, though it's > hard to see how that would work without something like `select`, which > didn't yet exist in 1978. Regardless, Unix still doesn't expose a > particularly convenient syntax for expressing these sorts of > constructions at the shell. Process substitution is about as close as we can get, but most programs still process their filename arguments one at a time, beginning to end. The canonical process substitution example is diff <(old-program-version) <(new-program-version) to do simple regression testing. -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/