mmap

#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>

int main(void) {
    int fd = open("main.c", O_RDONLY);
    char* data = mmap(NULL, 1024, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
    printf("%s", data);
    return 0;
}