Linux常用基本命令( touch )

touch命令:

作用：创建空文件，或者改变文件的时间戳属性

格式: touch [option] [file]

１，同时创建一个或者多个空文件

ghostwu@dev:~/linux/mkdir$ ls
ghostwu@dev:~/linux/mkdir$ touch a.txt
ghostwu@dev:~/linux/mkdir$ ls
a.txt
ghostwu@dev:~/linux/mkdir$ touch b.txt c.txt
ghostwu@dev:~/linux/mkdir$ ls
a.txt  b.txt  c.txt
ghostwu@dev:~/linux/mkdir$ touch {..}.txt
ghostwu@dev:~/linux/mkdir$ ls
.txt  .txt  .txt  .txt  .txt  a.txt  b.txt  c.txt

２，创建文件，并用stat查看文件的属性状态信息

ghostwu@dev:~/linux/mkdir$ touch ghostwu.txt
ghostwu@dev:~/linux/mkdir$ stat ghostwu.txt
  File: 'ghostwu.txt'
  Size:              Blocks:           IO Block:    regular empty file
Device: 807h/2055d    Inode:      Links:
Access: (/-rw-rw-r--)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::16.439856937 +
Modify: -- ::16.439856937 +
Change: -- ::16.439856937 +
 Birth: -

最后有３个时间

Access time:　最后访问时间，查看文件的内容时，这个时间会改变，使用cat命令查看文件时，可以看出Access time已经变了

ghostwu@dev:~/linux/mkdir$ stat ghostwu.txt
  File: 'ghostwu.txt'
  Size:              Blocks:           IO Block:    regular empty file
Device: 807h/2055d    Inode:      Links:
Access: (/-rw-rw-r--)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::16.439856937 +
Modify: -- ::16.439856937 +
Change: -- ::16.439856937 +
 Birth: -
ghostwu@dev:~/linux/mkdir$ cat ghostwu.txt
ghostwu@dev:~/linux/mkdir$ stat ghostwu.txt
  File: 'ghostwu.txt'
  Size:              Blocks:           IO Block:    regular empty file
Device: 807h/2055d    Inode:      Links:
Access: (/-rw-rw-r--)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::51.887215139 +
Modify: -- ::16.439856937 +
Change: -- ::16.439856937 +
 Birth: -

Modify time:最后修改时间，修改文件内容，文件的修改时间会改变。访问时间和状态改变时间　也发生变化

ghostwu@dev:~/linux/mkdir$ stat ghostwu.txt
  File: 'ghostwu.txt'
  Size:              Blocks:           IO Block:    regular empty file
Device: 807h/2055d    Inode:      Links:
Access: (/-rw-rw-r--)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::51.887215139 +
Modify: -- ::16.439856937 +
Change: -- ::16.439856937 +
 Birth: -
ghostwu@dev:~/linux/mkdir$ vim ghostwu.txt
ghostwu@dev:~/linux/mkdir$ stat ghostwu.txt
  File: 'ghostwu.txt'
  Size:              Blocks:           IO Block:    regular file
Device: 807h/2055d    Inode:      Links:
Access: (/-rw-rw-r--)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::34.982228802 +
Modify: -- ::34.982228802 +
Change: -- ::35.018231392 +
 Birth: -

Change time:状态改变时间,修改文件内容，移动文件，或者改变文件属性等，文件的change time会发生改变.

１，移动文件( 重命名 ), change time 发生改变:

ghostwu@dev:~/linux/mkdir$ stat ghostwu.txt
  File: 'ghostwu.txt'
  Size:              Blocks:           IO Block:    regular file
Device: 807h/2055d    Inode:      Links:
Access: (/-rw-rw-r--)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::34.982228802 +
Modify: -- ::34.982228802 +
Change: -- ::35.018231392 +
 Birth: -
ghostwu@dev:~/linux/mkdir$ mv ghostwu.txt ghostwu2.txt
ghostwu@dev:~/linux/mkdir$ stat ghostwu2.txt
  File: 'ghostwu2.txt'
  Size:              Blocks:           IO Block:    regular file
Device: 807h/2055d    Inode:      Links:
Access: (/-rw-rw-r--)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::34.982228802 +
Modify: -- ::34.982228802 +
Change: -- ::25.392863791 +

２，修改文件的权限，change time发生了改变

ghostwu@dev:~/linux/mkdir$ stat ghostwu2.txt
  File: 'ghostwu2.txt'
  Size:              Blocks:           IO Block:    regular file
Device: 807h/2055d    Inode:      Links:
Access: (/-rw-rw-r--)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::34.982228802 +
Modify: -- ::34.982228802 +
Change: -- ::25.392863791 +
 Birth: -
ghostwu@dev:~/linux/mkdir$ chmod  ghostwu2.txt
ghostwu@dev:~/linux/mkdir$ stat ghostwu2.txt
  File: 'ghostwu2.txt'
  Size:              Blocks:           IO Block:    regular file
Device: 807h/2055d    Inode:      Links:
Access: (/-rwxrwxrwx)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::34.982228802 +
Modify: -- ::34.982228802 +
Change: -- ::31.602584110 +
 Birth: -

touch -m修改文件的modify和change时间

ghostwu@dev:~/linux/mkdir$ stat ghostwu2.txt
  File: 'ghostwu2.txt'
  Size:              Blocks:           IO Block:    regular file
Device: 807h/2055d    Inode:      Links:
Access: (/-rwxrwxrwx)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::34.982228802 +
Modify: -- ::34.982228802 +
Change: -- ::31.602584110 +
 Birth: -
ghostwu@dev:~/linux/mkdir$ touch -m ghostwu2.txt
ghostwu@dev:~/linux/mkdir$ stat ghostwu2.txt
  File: 'ghostwu2.txt'
  Size:              Blocks:           IO Block:    regular file
Device: 807h/2055d    Inode:      Links:
Access: (/-rwxrwxrwx)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::34.982228802 +
Modify: -- ::31.678864985 +
Change: -- ::31.678864985 +

touch -d修改创建后的文件的修改时间

ghostwu@dev:~/linux/mkdir$ ls -lh ghostwu2.txt
-rwxrwxrwx  ghostwu ghostwu  5月    : ghostwu2.txt
ghostwu@dev:~/linux/mkdir$ touch -d  ghostwu2.txt
ghostwu@dev:~/linux/mkdir$ ls -lh ghostwu2.txt
-rwxrwxrwx  ghostwu ghostwu  2月     ghostwu2.txt
ghostwu@dev:~/linux/mkdir$ stat ghostwu2.txt
  File: 'ghostwu2.txt'
  Size:              Blocks:           IO Block:    regular file
Device: 807h/2055d    Inode:      Links:
Access: (/-rwxrwxrwx)  Uid: ( / ghostwu)   Gid: ( / ghostwu)
Access: -- ::00.000000000 +
Modify: -- ::00.000000000 +
Change: -- ::13.031347481 +
 Birth: -