#include <sys/types.h> #include <dlfcn.h> #include <error.h> #include <mcheck.h> #include <stdlib.h> #include <unistd.h> pid_t pid, pid2; pid_t getpid(void) { pid_t (*f)(void); f = (pid_t (*)(void)) dlsym (RTLD_NEXT, "getpid"); if (f == NULL) error (EXIT_FAILURE, 0, "dlsym (RTLD_NEXT, \"getpid\"): %s", dlerror ()); return (pid2 = f()) + 26; } int main (void) { pid_t (*f)(void); mtrace (); f = (pid_t (*)(void)) dlsym (RTLD_DEFAULT, "getpid"); if (f == NULL) error (EXIT_FAILURE, 0, "dlsym (RTLD_DEFAULT, \"getpid\"): %s", dlerror ()); pid = f(); if (pid != pid2 + 26) error (EXIT_FAILURE, 0, "main getpid() not called"); return 0; }