实验 5.2.8 解锁/锁定文件 1. 实现对指定文件的锁定和解锁。 1. 实现对指定文件的锁定和解锁。

实验 5.2.8 解锁/锁定文件
1. 实现对指定文件的锁定和解锁。
1. 实现对指定文件的锁定和解锁。
源代码：
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>

main()
{  
int fd,i;
char path[]="/root/txt1.txt";

fd=open(path,O_WRONLY|O_CREAT);
if(fd!=-1)
   { 
printf("opened file %s  .\n",path); 
if(flock(fd,LOCK_EX)==0)
      { 
printf("the file was locked.\n");
   } 
else
   { 
printf("the file was not locked.\n");
   } 

if(flock(fd,LOCK_UN)==0)
    { 
printf("the file was unlocked.\n");
    } 
else
   { 
printf("the file was not unlocked.\n");
   } 
close(fd);
   } 
else
   { 
printf("cant't open file %s.\n",path);
printf("errno：%d\n",errno);
printf("ERR  ：%s\n",strerror(errno));
   } 
}