fread
// from the linux programmer's manual, fread(3)
#include <stdio.h>
#include <stdlib.h>
int main()
{
FILE *fp = fopen("/bin/sh", "rb");
if (!fp) {
perror("fopen");
return EXIT_FAILURE;
}
unsigned char buffer[4];
size_t ret = fread(buffer, 4, 1, fp);
if (ret != sizeof(*buffer)) {
fprintf(stderr, "fread() failed: %zun", ret);
exit(EXIT_FAILURE);
}
printf("ELF magic: %#04x%02x%02x%02xn", buffer[0], buffer[1],
buffer[2], buffer[3]);
fclose(fp);
return 0;
}