命令說明：

touch  #建立檔案或更改檔案的時間戳

常用引數：

-a  #修改檔案的訪問時間(access),同時檔案的改變時間(change)也會更新

-m  #修改檔案的修改時間(modify),同時檔案的改變時間(change)也會更新

範例實踐：

#在/tmp目錄下和/root目錄下建立chenliang.txt檔案

[[email protected] ~]# touch /tmp/chenliang.txt /root/chenliang.txt

[[email protected] ~]# ll /tmp/chenliang.txt /root/chenliang.txt

-rw-r--r-- 1 root root 0 Nov 29 18:27 /root/chenliang.txt

-rw-r--r-- 1 root root 0 Nov 29 18:27 /tmp/chenliang.txt

#在/chenliang/目錄下建立liangliang01~10.txt檔案

[[email protected] ~]# mkdir /chenliang

[[email protected] ~]# touch /chenliang/liangliang{01..10}.txt

[[email protected] ~]# ll /chenliang/*

-rw-r--r-- 1 root root 0 Nov 29 18:32 /chenliang/liangliang01.txt

-rw-r--r-- 1 root root 0 Nov 29 18:32 /chenliang/liangliang02.txt

-rw-r--r-- 1 root root 0 Nov 29 18:32 /chenliang/liangliang03.txt

-rw-r--r-- 1 root root 0 Nov 29 18:32 /chenliang/liangliang04.txt

-rw-r--r-- 1 root root 0 Nov 29 18:32 /chenliang/liangliang05.txt

-rw-r--r-- 1 root root 0 Nov 29 18:32 /chenliang/liangliang06.txt

-rw-r--r-- 1 root root 0 Nov 29 18:32 /chenliang/liangliang07.txt

-rw-r--r-- 1 root root 0 Nov 29 18:32 /chenliang/liangliang08.txt

-rw-r--r-- 1 root root 0 Nov 29 18:32 /chenliang/liangliang09.txt

-rw-r--r-- 1 root root 0 Nov 29 18:32 /chenliang/liangliang10.txt

#修改/chenliang/liangliang01.txt檔案的訪問時間（訪問時間的更新，改變時間也會隨著更新）

[[email protected] ~]# stat /chenliang/liangliang01.txt

File: `/chenliang/liangliang01.txt'

Size: 0 Blocks: 0 IO Block: 4096 regular empty file

Device: 803h/2051d Inode: 1177349 Links: 1

Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)

Access: 2018-11-29 18:32:53.644717804 +0800

Modify: 2018-11-29 18:32:53.644717804 +0800

Change: 2018-11-29 18:32:53.644717804 +0800

[[email protected] ~]# touch -a /chenliang/liangliang01.txt

[[email protected] ~]# stat /chenliang/liangliang01.txt

File: `/chenliang/liangliang01.txt'

Size: 0 Blocks: 0 IO Block: 4096 regular empty file

Device: 803h/2051d Inode: 1177349 Links: 1

Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)

Access: 2018-11-29 18:36:35.675763737 +0800

Modify: 2018-11-29 18:32:53.644717804 +0800

Change: 2018-11-29 18:36:35.675763737 +0800

#修改/chenliang/liangliang02.txt檔案的修改時間（修改時間的更新，改變時間也會隨著更新）

[[email protected] ~]# stat /chenliang/liangliang02.txt

File: `/chenliang/liangliang02.txt'

Size: 0 Blocks: 0 IO Block: 4096 regular empty file

Device: 803h/2051d Inode: 1177350 Links: 1

Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)

Access: 2018-11-29 18:32:53.644717804 +0800

Modify: 2018-11-29 18:32:53.644717804 +0800

Change: 2018-11-29 18:32:53.644717804 +0800

[[email protected] ~]# touch -m /chenliang/liangliang02.txt

[[email protected] ~]# stat /chenliang/liangliang02.txt

File: `/chenliang/liangliang02.txt'

Size: 0 Blocks: 0 IO Block: 4096 regular empty file

Device: 803h/2051d Inode: 1177350 Links: 1

Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)

Access: 2018-11-29 18:32:53.644717804 +0800

Modify: 2018-11-29 18:40:22.144336030 +0800

Change: 2018-11-29 18:40:22.144336030 +0800