mygetenv
char *mygetenv(char *variable, char *deflt);
editor = mygetenv("EDITOR", EDITOR);
editor = mygetenv("VIEWER", editor); /* use viewer if set */
shell = mygetenv("SHELL", SHELL);
tmpdir = mygetenv("TMPDIR", TMPDIR);
cscopedepth = atoi(mygetenv("CSCOPEDEPTH", "0"));