Divergence from original devloper's pkg
The first point of divergence is that the original pkg is oriented toward generic posix shell and this line supports the mcpcms variant of zsh.
Ultimately I expect this code to evolve into WFL. Something drastic will be done early on to get closer to my original intent of a synthesis of cl and (an actual) shell (e.g. mcpcms) vs the source pkg which is more of a posix shell emulation in lisp that can exec.
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