system("./SHELL");
print "by the time you see this, you'll have exited the shell";

##</code><code>##

#invokes SHELL, then waits until termination of console
#to call CMD...not what i need
system("./SHELL\nCMD\n");

#invokes the SHELL, enters command into SHELL,
#then terminates SHELL before user can do anything
system("./SHELL<<EOC\nCMD\nEOC\n");