沈雅

本示例演示Linux下read open write 函数的使用方法。用于从filecp.txt文件复制内容到filecp1.txt。

代码如下：

//******************************************

//Linux system API progrems example

//shenya&yexing

//20150409

//******************************************

#include<stdio.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <stdio.h>

#include <unistd.h>

//upon is headfiles

int main()

{

int a=0,b=0,c=0,d=0;

char q[30];

a = open("/home/filecp.txt",O_RDWR|O_CREAT,0777);  //openfilecp.txt

if(a==-1)

{

printf("open shibai!\n");

}

        else

{

printf("open chenggong!\n");

printf("%d\n",a);

}

c = read(a,q,29);  //reading data to value q

q[29]='\0';

if(a==-1)

{

printf("read shibai!\n");

}

        else

{

printf("read chenggong!\n");

}

close(a);    //close the file

b = open("/home/filecp1.txt",O_RDWR|O_CREAT,0777); //open filecp1

if(b==-1)

{

printf("open shibai!\n");

}

        else

{

printf("open chenggong!\n");

printf("%d\n",b);

}

d = write(b,q,30);  //writting data to filecp1.txt from volue q

if(d==-1)

{

printf("write shibai!\n");

}

        else

{

printf("write chenggong!\n");

}

close(b); //close this files

        return 0;

}