二进制文件的读写问题

为啥会产生两种结果啊？？40和140这两个数应该不会写到文件里面啊，我写的i<40和i<140啊！求解

#include <stdio.h>
#include <stdint.h>     // included for uint8_t

int main(int argc, char const *argv[]) {
    uint8_t buf[4096] = {0x00};
    FILE *fp = fopen("/usr/bin/prince", "r");
    size_t size = fread(buf, 1, 4096, fp);
    fclose(fp);
    return 0;
}