Linux 获取文件大小--C函数

#include <sys/stat.h>
unsigned long get_file_size(const char *path)
{
    unsigned long filesize = -1;
    struct stat statbuff;
    if(stat(path, &statbuff) < 0){
        return filesize;
    }else{
        filesize = statbuff.st_size;
    }
    return filesize;
}