c 中获得文件长度的示例

#include <stdlib.h>
#include <stdio.h>
int main()
{
    FILE* inFile=fopen( "test_in.txt ", "rb");
    FILE* outFile=fopen( "test_out.txt ", "wb+");
    int buffsize;
    char* buffer;
    if(inFile!=NULL)
    {
        buffsize=fseek(inFile,0,SEEK_END)-fseek(inFile,0,SEEK_SET);
        fseek(inFile,0,SEEK_SET);
        buffer=(char*)malloc(buffsize*sizeof(char));
        fread(buffer,buffsize,1,inFile);
        fwrite(buffer,buffsize,1,outFile);
    }else{
        fprintf(stderr, "error ");
    }
}