11.7 文件IO

XMIND

#include <myhead.h>
int main(int argc, const char *argv[])
{
	int fd = open("./1.txt",O_RDWR|O_CREAT,0664);
	if(fd==-1)
	{
		perror("open");
		return -1;
	}
	
	int fd1 = open("./2.txt",O_RDWR|O_CREAT,0664);
	if(fd1==-1)
	{
		perror("open");
		return -1;
	}
	
	char str[] = "欢迎来到c语言的世界";
	char s[100];
	int len = write(fd,str,sizeof(str));
	int l = lseek(fd,0,SEEK_END);
	lseek(fd,0,SEEK_SET);
	read(fd,s,l);
	printf("1.txt的内容是：%s\n",s);
	write(fd1,s,l);

	close(fd);
	close(fd1);

	return 0;
}

运行：