c语言获取文件长度的方法

#include<stdio.h>

int GetFileLen(unsigned char * FileName)

{

    FILE * file;

    int len =  0;

    file = fopen(FileName, "r");

    fseek(file, 0L, SEEK_END);

    len = ftell(file);

    fseek(file, 0L, SEEK_SET);

    return len;

}