OpenExtensions for z/VM "Q"s and "A"s

Question: Under many UNIX systems we access the environment variable table via a parameter (envp) which is passed to a main program on the initial call. Under OpenExtensions this seems not to exist. How do I find the value of all environment variables which have been set in the shell prior to calling a program when I don't know the names of these variables? If I did, then I could obviously use getenv().

Response: There is no third parameter (envp) to main() in OpenExtensions. Its use is not portable. A more portable method is using the external environ array. So if you have code like the following:

 main(int argc, char **argv, char **envp)

 extern char **environ;
 #define envp environ
 
 main(int argc, char **argv)

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