Function read_u64

server/src/server/disk_prefix_cache.cpp:183–183

static bool read_u32(FILE * f, uint32_t & out) { return std::fread(&out, 4, 1, f) == 1; }
static bool read_u64(FILE * f, uint64_t & out) { return std::fread(&out, 8, 1, f) == 1; }
static bool read_i64(FILE * f, int64_t & out)  { return std::fread(&out, 8, 1, f) == 1; }
static bool read_u16(FILE * f, uint16_t & out) { return std::fread(&out, 2, 1, f) == 1; }