文件数据块读取写入实现文件复制功能

size_t fread ( void *ptr, size_t size, size_t count, FILE *fp );

size_t fwrite ( void * ptr, size_t size, size_t count, FILE *fp );
用到的函数原型

#include <stdio.h>
#include<stdlib.h>

char* CopyFile(char* fileRead,char* fileWrite)
{
        FILE* fpRead;
        FILE* fpWrite;
        int bufferLen=1024*4;
        char* buffer=(char*)malloc(bufferLen);
        int readCount;

        if((fpRead=fopen(fileRead,"rb"))==NULL||(fpWrite=fopen(fileWrite,"wb"))==NULL)
        {
                printf("error\n");
                char ch=getchar();
                return (char*)"error";
        }

        while((readCount=fread(buffer,1,bufferLen,fpRead))>0)
                fwrite(buffer,1,readCount,fpWrite);

        free(buffer);
        fclose(fpRead);
        fclose(fpWrite);
        return nullptr;
}
int main(int argc,char* argv[])
{
        if(CopyFile(argv[1],argv[2])==nullptr)
                printf("copy file success\n");
        else
                printf("copy file fail\n");
        return 0;
}

编译

sudo g++ copyFile.cc -o copyFile.exe

 

 将copy_file1.txt内容拷贝到copy_file2.txt中