4.3BSD - /usr/src/ucb/dbx/tests/noenv.c

   1: /*
   2:  * Exec a program with no environment.
   3:  */
   4: 
   5: #include <stdio.h>
   6: 
   7: extern int errno;
   8: extern char *getenv(), *index();
   9: 
  10: main (argc, argv)
  11: int argc;
  12: char *argv[];
  13: {
  14:     execvep(argv[1], &argv[1], 0);
  15:     printf("exec failed, errno %d\n", errno);
  16: }
  17: 
  18: execvep (name, argv, envp)
  19: char *name, *argv[], *envp[];
  20: {
  21:     char *path;
  22:     register char *cp;
  23:     char fullname[1000];
  24: 
  25:     path = getenv("PATH");
  26:     if (path == NULL) {
  27:     path = "";
  28:     cp = NULL;
  29:     } else {
  30:     cp = index(path, ':');
  31:     }
  32:     for (;;) {
  33:     if (cp != NULL) {
  34:         *cp = '\0';
  35:     }
  36:     sprintf(fullname, "%s/%s", path, name);
  37:     execve(fullname, argv, envp);
  38:     if (cp != NULL) {
  39:         path = cp + 1;
  40:         cp = index(path, ':');
  41:     } else {
  42:         break;
  43:     }
  44:     }
  45:     return -1;
  46: }

Defined functions