#include <assert.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <unistd.h>
#include <string>
#ifndef MAP_FILE
#define MAP_FILE 0
#endif
char array[4096];
int main(int argc, char **argv) {
int fd = open((std::string(argv[0]) + ".m").c_str(), O_RDWR | O_CREAT, 0700);
if (fd < 0) {
perror("open");
exit(1);
}
assert(write(fd, array, sizeof(array)) == sizeof(array));
char *addr = (char *)mmap(nullptr, sizeof(array), PROT_READ,
MAP_FILE | MAP_SHARED, fd, 0);
if (addr == MAP_FAILED) {
perror("mmap");
exit(1);
}
assert(ftruncate(fd, 0) == 0);
return addr[42];
}