understanding requirements for execve and setting environment vars

Question

We are having a lot of trouble interpreting our teacher. We asked for clarification and got the following back from him

1. For execve, send it a environment you se

Answer 1

The code from Jonathan Leffler works great, except if you want to change the PWD (working directory) variable.

What I did, in order to change the working directory, was to put a chdir(..) before execve(..) and call:

chdir("/foo/bar"); 
execve(argv[0], &argv[0], envp);