Handy functions for reading integers out of a file with network byte order. Packaged in a header file for inlining.

ReadOut.h

#ifndef READ_OUT_H_GUARD
#define READ_OUT_H_GUARD

#include <stdint.h>
#include <cstdio>
#include "./fileindexutil.h"


uint64_t read64(FILE* file) {
  uint64_t out;
  fread(&out, sizeof(out), 1, file);
  return ntohll(out);
}

uint32_t read32(FILE* file) {
  uint32_t out;
  fread(&out, sizeof(out), 1, file);
  return ntohl(out);
}

uint16_t read16(FILE* file) {
  uint16_t out;
  fread(&out, sizeof(out), 1, file);
  return ntohs(out);
}

uint8_t read8(FILE* file) {
  uint8_t out;
  fread(&out, sizeof(out), 1, file);
  return out;
}

#endif // READ_OUT_H_GUARD

usage.c

// somewhere in your code
uint32_t magic_number = read32(file_);