复制使用FREAD和fwrite二进制文件 [英] Copying binary files using fread and fwrite

问题描述

使用复制二进制文件时，我有一个问题 FREAD 和 FWRITE ：
环路仅运行两次（40个字节），但该文件长度是160字节

 的#include＆LT;＆string.h中GT;
＃定义PER_READ 30
INT主要（无效）
{    字符缓冲区[500] = {0};
    FILE * CSV =的fopen（CSV.csv，RB）;
    FILE * csvDest =的fopen（CSVDest.csv，世行）;
    unsigned int类型成品= 0;
    无符号整型计数器= 0;
    做
    {
        成品= FREAD（缓冲区的sizeof（字符*），PER_READ，CSV）; //从CSV阅读所有以一个字符串名称缓冲区
        成品+ = PER_READ *计数器;
        反++;
    }而（完== PER_READ *计数器）;
    FWRITE（缓冲区的sizeof（字符*），成品，csvDest）; //写入所有到一个文件CSVDest    系统（暂停）;
    返回（0）;
};
 

解决方案

 的#include＆LT;＆string.h中GT;
＃包括LT＆;＆stdio.h中GT;
＃定义PER_READ 30
INT主要（无效）
{
    字符缓冲区[500] = {0};
    FILE * CSV =的fopen（CSV.csv，RB）;
    FILE * csvDest =的fopen（CSVDest.csv，世行）;
    unsigned int类型成品= 0;
    无符号整型计数器= 0;
    unsigned int类型numBlocksRead = 0;
    做
    {
        numBlocksRead = FREAD（缓冲区的sizeof（炭），PER_READ，CSV）;
        成品+ = numBlocksRead * sizeof的（字符）;
        反++;
        FWRITE（缓冲区的sizeof（炭），numBlocksRead，csvDest）;    }而（完== PER_READ *计数器）;    FCLOSE（CSV）;
    FCLOSE（csvDest）;
    系统（暂停）;
    返回（0）;
}
 

I have a problem when copying binary files using fread and fwrite: the loop runs only two times (40 bytes), but the file length is 160 bytes:

#include <string.h>
#define PER_READ 30
int main(void)
{

    char buffer[500] = { 0 };
    FILE* CSV = fopen( "CSV.csv", "rb" );
    FILE* csvDest = fopen( "CSVDest.csv", "wb" );
    unsigned int finished = 0;
    unsigned int counter = 0;
    do
    {
        finished = fread( buffer, sizeof( char*), PER_READ, CSV );//Read all from CSV to a string name buffer
        finished += PER_READ * counter;
        counter++;
    } while (finished == PER_READ * counter);
    fwrite( buffer, sizeof( char* ), finished, csvDest );// write all to a the file CSVDest

    system( "PAUSE" );
    return (0);
};

解决方案

    #include <string.h>
#include <stdio.h>
#define PER_READ 30
int main( void )
{
    char buffer[500] = { 0 };
    FILE* CSV = fopen( "CSV.csv", "rb" );
    FILE* csvDest = fopen( "CSVDest.csv", "wb" );
    unsigned int finished = 0;
    unsigned int counter = 0;
    unsigned int numBlocksRead = 0;
    do
    {
        numBlocksRead = fread( buffer, sizeof( char ), PER_READ, CSV );
        finished += numBlocksRead*sizeof( char );
        counter++;
        fwrite( buffer, sizeof( char ), numBlocksRead, csvDest );

    } while (finished == PER_READ * counter);

    fclose( CSV );
    fclose( csvDest );
    system( "PAUSE" );
    return (0);
}

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