[grosskur]

You can simulate this with so-called "Bernstein chaining". Basically, each program takes another program as an argument, and finishes by calling exec() on it rather than exit(), which preserves the environment. See:

http://www.catb.org/~esr/writings/taoup/html/ch06s06.html

Or write environment variables to stdout in Bourne shell syntax so the caller call run "eval" on it. Like ssh-agent, for example.

[gohrt]

Continuation Passing Style! http://en.wikipedia.org/wiki/Continuation-passing_style

[agumonkey]

Oh wow, unix continuation passing style. Never heard of that o_o;