I have a Linux kernel hack which causes special behavior based on a process's environment. Strangely, unix kernels are aware of each process's environment, and with Linux it is visible as /proc/*/environ. The hack works wonderfully.

My problem is I am writing test regression scripts in perl. Modifying %ENV doesn't actually call setenv() to change it for the OS to see, thus my kernel trick is not tested. How can I make perl "flush" the environment?

The perlvar man page says fork() causes the children to receive environment updates, but in my testing it is exec() which does the magic. Damn.

Sadly, calling system() or qx// or something that calls exec() does not flush the environment of the parent, only the child. :-(

In other words, I challenge you to modify /proc/self/environ in perl without calling exec().

In reply to true environment by tallfred

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