8.7 Process Substitution A unique but rarely used feature of bash is process substitution Let's say that you had two versions of a program that produced large quantities of output You want to see the differences between the output from each version You could run the two programs, redirecting their output to files, and then use the cmp utility to see what the differences were Another way would be to use process substitution There are two forms of this substitution One is for input to a process: >(list); the other is for output from a process: