linux--文件写入整数和结构体数组

文件写入整数：

#include 
#include 
#include 
#include 
#include 
#include 
#include 

int main()
{
	int fd;
	int data1 = 100;
	int data2 = 0;
	
	fd = open("./file1",O_RDWR);//打开文件以读写的权限

	int n_write =write(fd,&data1,sizeof(int));
		
	lseek(fd,0,SEEK_SET);
	
	int n_read = read(fd,&data2,sizeof(int));
	
	printf("read: %d\n",data2);
	close(fd);
	
	return 0;
}

写入结构体：

#include 
#include 
#include 
#include 
#include 
#include 
#include 

struct Test
{
	int a;
	char c;
};

int main()
{
	int fd;
	struct Test data1 = {100,'a'};
	struct Test data2;
	
	fd = open("./file2",O_RDWR);//打开文件以读写的权限

	int n_write =write(fd,&data1,sizeof(struct Test ));
		
	lseek(fd,0,SEEK_SET);
	
	int n_read = read(fd,&data2,sizeof(struct Test ));
	
	printf("read: %d,%c \n",data2.a,data2.c);
	close(fd);
	
	return 0;
}

写入数组：

#include 
#include 
#include 
#include 
#include 
#include 
#include 

struct Test
{
	int a;
	char c;
};

int main()
{
	int fd;
	struct Test data1[2] = {100,'a'},{101,'b'};
	struct Test data2[2];
	
	fd = open("./file3",O_RDWR);//打开文件以读写的权限

	int n_write =write(fd,&data1,sizeof(struct Test )*2);
		
	lseek(fd,0,SEEK_SET);
	
	int n_read = read(fd,&data2,sizeof(struct Test )*2);
	
	printf("read: %d,%c \n",data2[0].a,data2[0].c);
	printf("read: %d,%c \n",data2[1].a,data2[1].c);
	close(fd);
	
	return 0;
}