The time of the Linux file record

Production found a problem, find the root cause is because the file was modified, and then by looking at the modified time, the rights of the user, find the operation of the machine, which found a point is the Linux file time record, there are three access (access), Modfiy (vi Edit), change (Modify permissions)

Commonly viewed as stat filename and ls-l--full-time filename

1, when we just read the file, access time changes, and Modify,change does not change

2, Access,modify,change time will change when the file is modified

3, change time changes when file attributes are modified, and access,modify is unchanged

So with this in mind, touch can completely change the time you move files, and what you see is not real.

[Email protected] ~]# stat 3.sql
File: ' 3.sql '
size:2126 blocks:8 IO block:4096 Regular file
device:802h/2050d inode:652821 links:1
Access: (0755/-rwxr-xr-x) Uid: (0/root) Gid: (0/root)
Access: 2016-08-28 18:08:26.571999874 +0800--accurate to millisecond level
Modify: 2016-08-28 18:08:26.571999874 +0800
Change: 2016-08-28 18:08:26.575999780 +0800
[Email protected] ~]#Cat 3.sql
-MySQL dump 10.13 distrib 5.5.22, for Linux (i686)
--
--host:192.168.4.11 Database:test
-- ------------------------------------------------------
--Server version 5.5.22-log
。。。。。。。。
[Email protected] ~]# stat 3.sql
File: ' 3.sql '
size:2126 blocks:8 IO block:4096 Regular file
device:802h/2050d inode:652821 links:1
Access: (0755/-rwxr-xr-x) Uid: (0/root) Gid: (0/root)
Access: 2016-08-28 18:18:50.937999994 +0800--because just after the cat was executed, it changed only
Modify:2016-08-28 18:08:26.571999874 +0800
Change:2016-08-28 18:08:26.575999780 +0800

[Email protected] ~]#VI 3.sql
-MySQL dump 10.13 distrib 5.5.22, for Linux (i686)
--
--host:192.168.4.11 Database:test
-- ------------------------------------------------------
--Server version 5.5.22-log
。。。。。。。。 [Email protected] ~]# stat 3.sql
File: ' 3.sql '
size:2127 blocks:8 IO block:4096 Regular file
device:802h/2050d inode:652820 links:1
Access: (0755/-rwxr-xr-x) Uid: (0/root) Gid: (0/root)
Access: 2016-08-28 18:20:36.679998313 +0800---can see the VI is changed
Modify: 2016-08-28 18:20:36.679998313 +0800
Change: 2016-08-28 18:20:36.696998878 +0800
[Email protected] ~]#chmod o+w 3.sql
[Email protected] ~]# stat 3.sql
File: ' 3.sql '
size:2127 blocks:8 IO block:4096 Regular file
device:802h/2050d inode:652820 links:1
Access: (0757/-rwxr-xrwx) Uid: (0/root) Gid: (0/root)
Access:2016-08-28 18:20:36.679998313 +0800
Modify:2016-08-28 18:20:36.679998313 +0800
Change: 2016-08-28 18:21:43.217999570 +0800
[Email protected] ~]#

[[email protected] ~]# Info Touch--This thing can not only create a file but also change the file time

Time stamps.

The program accepts the following options. Also See *note Common
Options::.

'-A '
'--time=atime '
'--time=access '
'--time=use '
Change the access time only .

[Email protected] ~]# stat 3.sql
File: ' 3.sql '
size:2127 blocks:8 IO block:4096 Regular file
device:802h/2050d inode:652820 links:1
Access: (0757/-rwxr-xrwx) Uid: (0/root) Gid: (0/root)
Access:2016-08-28 18:24:23.473989642 +0800
Modify:2016-08-28 18:24:23.473989642 +0800
Change:2016-08-28 18:24:23.473989642 +0800
[Email protected] ~]#touch-a 3.sql---plus parameter-a
[Email protected] ~]# stat 3.sql
File: ' 3.sql '
size:2127 blocks:8 IO block:4096 Regular file
device:802h/2050d inode:652820 links:1
Access: (0757/-rwxr-xrwx) Uid: (0/root) Gid: (0/root)
Access: 2016-08-28 18:24:34.580998824 +0800
Modify:2016-08-28 18:24:23.473989642 +0800
change:2016-08-28 18:24:34.580998824 +0800

[Email protected] ~]# stat 3.sql
File: ' 3.sql '
size:2127 blocks:8 IO block:4096 Regular file
device:802h/2050d inode:652820 links:1
Access: (0757/-rwxr-xrwx) Uid: (0/root) Gid: (0/root)
Access:2016-08-28 18:24:34.580998824 +0800
Modify:2016-08-28 18:24:23.473989642 +0800
Change:2016-08-28 18:24:34.580998824 +0800
[Email protected] ~]#
[Email protected] ~]#Touch 3.sql--Wood with additional parameters
[Email protected] ~]# stat 3.sql
File: ' 3.sql '
size:2127 blocks:8 IO block:4096 Regular file
device:802h/2050d inode:652820 links:1
Access: (0757/-rwxr-xrwx) Uid: (0/root) Gid: (0/root)
Access: 2016-08-28 18:28:26.230998361 +0800
Modify: 2016-08-28 18:28:26.230998361 +0800
Change: 2016-08-28 18:28:26.230998361 +0800
[Email protected] ~]#

This article from "Yun Weibang" blog, declined reprint!

The time of the Linux file record