Linux C 中 open close read write 使用实例

这里实现的是将文件cody.txt中的内容拷贝到to_cody.txt中去。



 1 /*
 ============================================================================
 Name        : FileIO.c
 Author      : Cody
 Version     :
 Copyright   : Written By Cody
 Description :
 ============================================================================
 */

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


#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <unistd.h>

int main(int argc,char *argv[]) {

    int fromFd = open("/root/cody.txt",O_RDONLY);
    if(fromFd == -1)
    {
        perror("打开From文件");
        exit(0);
    }

    int toFd = open("/root/to_cody.txt",O_WRONLY | O_CREAT);
    if(toFd == -1)
    {
        perror("打开To文件");
        exit(0);
    }

    read_To_File(fromFd,toFd);

    close(fromFd);
    close(toFd);

    return EXIT_SUCCESS;
}


/**
 * 将一个文件的内容，写入到另一个文件
 */
int read_To_File(int fromFd,int toFd)
{

    char buf[512];

    int readBytes;

    int writeBytes;

    if(fromFd == -1 || toFd == -1) return -1;

    memset(buf,0,sizeof(buf));
    printf("开始读写\n");
    while((readBytes = read(fromFd,buf,sizeof(buf))) > 0)
    {
        puts(buf);

        writeBytes = write(toFd,buf,readBytes);

        if(writeBytes == -1)
        {
            perror("write error");
        }

        memset(buf,0,sizeof(buf));
    }

    return 1;
}