1 #include <stdlib.h> 2 #include <sys/types.h> 3 #include <unistd.h> 4 5 6 /* check for whether caller is a specific uid (numeric) */ 7 8 int main(int argc,char * argv[])9main(int argc, char *argv[]) 10 { 11 int uid = 0; 12 13 if (argc > 1) 14 uid = atoi(argv[1]); 15 16 exit(getuid() == uid ? 0 : 1); 17 } 18