find -atime -ctime -mtime区别

find -atime -ctime -mtime区别


atime、mtime与ctime的区别


access time  ， atime在读取文件或执行文件时会修改
create time  ， ctime在文件写入，更改所有者，权限。链接时文件的ctime会随之改变
modified time ，mtime 在文件写入时会改变。

ls -lu  或者 ls -l --time=atime 显示文件的atime
ls -lc 或者  ls -l --time=ctime 显示文件的ctime
ls -l    显示文件的mtime






[root@station206 test]# touch test.txt
[root@station206 test]# stat test.txt
  File: `test.txt'
  Size: 0               Blocks: 8          IO Block: 4096   regular

empty file
Device: fd00h/64768d    Inode: 1179651     Links: 1
Access: (0644/-rw-r--r--)  Uid: (    0/    root)   Gid: (    0/   

root)
Access: 2009-05-21 01:46:26.000000000 +0800         ## atime
Modify: 2009-05-21 01:46:26.000000000 +0800         ## mtime
Change: 2009-05-21 01:46:26.000000000 +0800        ## ctime

[root@station206 test]# more test.txt              ## 访问文件
[root@station206 test]# stat test.txt
  File: `test.txt'
  Size: 0               Blocks: 8          IO Block: 4096   regular

empty file
Device: fd00h/64768d    Inode: 1179651     Links: 1
Access: (0644/-rw-r--r--)  Uid: (    0/    root)   Gid: (    0/   

root)
Access: 2009-05-21 01:47:21.000000000 +0800           ## atime有变法了
Modify: 2009-05-21 01:46:26.000000000 +0800
Change: 2009-05-21 01:46:26.000000000 +0800

[root@station206 test]# echo asdf > test.txt          ## 添加内容
[root@station206 test]# stat test.txt       
  File: `test.txt'
  Size: 5               Blocks: 16         IO Block: 4096   regular

file
Device: fd00h/64768d    Inode: 1179651     Links: 1
Access: (0644/-rw-r--r--)  Uid: (    0/    root)   Gid: (    0/   

root)
Access: 2009-05-21 01:47:21.000000000 +0800           ## atime没有变法

，疑问？
Modify: 2009-05-21 01:48:14.000000000 +0800           ## mtime有变法
Change: 2009-05-21 01:48:14.000000000 +0800        ## ctime有变法


[root@station206 test]# chmod a+x test.txt         ## 修改属性
[root@station206 test]# stat test.txt     
  File: `test.txt'
  Size: 5               Blocks: 16         IO Block: 4096   regular

file
Device: fd00h/64768d    Inode: 1179651     Links: 1
Access: (0755/-rwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/   

root)
Access: 2009-05-21 01:47:21.000000000 +0800        ## atime没有变

法
Modify: 2009-05-21 01:48:14.000000000 +0800        ## mtime没有变

法
Change: 2009-05-21 01:49:39.000000000 +0800        ## ctime有变法

[root@station206 test]# vim test.txt             ## 编辑文件
[root@station206 test]# stat test.txt
  File: `test.txt'
  Size: 12              Blocks: 16         IO Block: 4096   regular

file
Device: fd00h/64768d    Inode: 1179653     Links: 1
Access: (0755/-rwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/   

root)
Access: 2009-05-21 01:50:55.000000000 +0800
Modify: 2009-05-21 01:50:55.000000000 +0800
Change: 2009-05-21 01:50:55.000000000 +0800        ## 都发生变法


[root@station206 test]# mv test.txt test.txt2
[root@station206 test]# stat test.txt       
stat: cannot stat `test.txt': No such file or directory
[root@station206 test]# stat test.txt2
  File: `test.txt2'
  Size: 12              Blocks: 16         IO Block: 4096   regular

file
Device: fd00h/64768d    Inode: 1179653     Links: 1
Access: (0755/-rwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/   

root)
Access: 2009-05-21 01:50:55.000000000 +0800
Modify: 2009-05-21 01:50:55.000000000 +0800
Change: 2009-05-21 01:51:52.000000000 +0800        ##只有ctime发

生变法





atime 访问时间(access time)：访问时间是文件最后一次被读取的时间。因此

阅读一个文件会更新它的访问时间，而它的改变时间并没有变化(有关文件状态

的信息没有被改变)，它的修改时间也同样没有变化(文件内容本身没有被改变)

；

mtime 修改时间(modification time)：文件内容最后被修改的时间。

ctime 改变时间(change time)：文件状态（status）最后被改变的时间。




[root@station206 test]# touch -at 200701010000 test.txt2
[root@station206 test]# stat test.txt2                  
  File: `test.txt2'
  Size: 12              Blocks: 16         IO Block: 4096   regular

file
Device: fd00h/64768d    Inode: 1179653     Links: 1
Access: (0755/-rwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/   

root)
Access: 2007-01-01 00:00:00.000000000 +0800
Modify: 2009-05-21 01:50:55.000000000 +0800
Change: 2009-05-21 01:53:57.000000000 +0800
[root@station206 test]# touch -mt 200701010000 test.txt2 
[root@station206 test]# stat test.txt2                  
  File: `test.txt2'
  Size: 12              Blocks: 16         IO Block: 4096   regular

file
Device: fd00h/64768d    Inode: 1179653     Links: 1
Access: (0755/-rwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/   

root)
Access: 2007-01-01 00:00:00.000000000 +0800
Modify: 2007-01-01 00:00:00.000000000 +0800
Change: 2009-05-21 01:54:07.000000000 +0800
[root@station206 test]# touch -ct 200701010000 test.txt2 
[root@station206 test]# stat test.txt2                  
  File: `test.txt2'
  Size: 12              Blocks: 16         IO Block: 4096   regular

file
Device: fd00h/64768d    Inode: 1179653     Links: 1
Access: (0755/-rwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/   

root)
Access: 2007-01-01 00:00:00.000000000 +0800
Modify: 2007-01-01 00:00:00.000000000 +0800
Change: 2009-05-21 01:54:12.000000000 +0800

## touch改不了ctime？可能只能修改系统时间才能修改ctime了。