touch:触摸
命令作用：
用来修改文件的时间戳或创建一个文件；
2.命令格式：
touch [options] file
3.参数说明：
-a：access（访问）修改访问时间；
-m：modify（修改）修改内容改变时间；
-t：time（时间）指定修改时间， [[CC]YY]MMDDhhmm[.SS]；
-c：no create(不创建)不创建文件；
-r：把指定文件或目录的时间戳统统设定成参考文件或目录的时间戳，touch -r 参考 指定；
4.范例：
[root@localhost ~]# touch a
[root@localhost ~]# ll a
-rw-r--r--. 1 root root 0 Oct 15 22:27 a
[root@localhost ~]# stat a //stat用于查看文件状态信息；
File: `a'
Size: 0 Blocks: 0 IO Block: 4096 regular empty file
Device: fd00h/64768dInode: 277116 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2016-10-15 22:27:16.913734004 +0800
Modify: 2016-10-15 22:27:16.913734004 +0800
Change: 2016-10-15 22:27:16.913734004 +0800
[root@localhost ~]# touch -m a
[root@localhost ~]# stat a
File: `a'
Size: 0 Blocks: 0 IO Block: 4096 regular empty file
Device: fd00h/64768dInode: 277116 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2016-10-15 22:27:16.913734004 +0800
Modify: 2016-10-15 22:28:56.719990522 +0800
Change: 2016-10-15 22:28:56.719990522 +0800
[root@localhost ~]# touch -a a
[root@localhost ~]# stat a
File: `a'
Size: 0 Blocks: 0 IO Block: 4096 regular empty file
Device: fd00h/64768dInode: 277116 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2016-10-15 22:30:00.173980242 +0800
Modify: 2016-10-15 22:28:56.719990522 +0800
Change: 2016-10-15 22:30:00.173980242 +0800
[root@localhost ~]# touch -t 208811112222.43 a
[root@localhost ~]# stat a
File: `a'
Size: 0 Blocks: 0 IO Block: 4096 regular empty file
Device: fd00h/64768dInode: 277116 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2088-11-11 22:22:43.000000000 +0800
Modify: 2088-11-11 22:22:43.000000000 +0800
Change: 2016-10-15 22:32:12.292220034 +0800
[root@localhost ~]# touch -c b
[root@localhost ~]# ll
total 104
-rw-r--r--. 1 root root 0 Nov 11 2088 a
-rw-------. 1 root root 1645 Mar 16 2016 anaconda-ks.cfg
-rw-r--r--. 1 root root 50101 Mar 16 2016 install.log
-rw-r--r--. 1 root root 10608 Mar 16 2016 install.log.syslog
[root@localhost ~]# touch -r a b
[root@localhost ~]# stat a
File: `a'
Size: 0 Blocks: 0 IO Block: 4096 regular empty file
Device: fd00h/64768dInode: 277116 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2088-11-11 22:22:43.000000000 +0800
Modify: 2088-11-11 22:22:43.000000000 +0800
Change: 2016-10-15 22:32:12.292220034 +0800
[root@localhost ~]# stat b
File: `b'
Size: 0 Blocks: 0 IO Block: 4096 regular empty file
Device: fd00h/64768dInode: 277121 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2088-11-11 22:22:43.000000000 +0800
Modify: 2088-11-11 22:22:43.000000000 +0800
Change: 2016-10-15 22:33:55.168001206 +0800
rm:remove删除
命令作用：
删除目录中的一个或多个文件或目录；
2.命令格式：
rm [options] file or directory
3.参数说明：
-f:force(强迫)强行删除，不给出提示；
-i:interactive(互动)进行交互式删除，有提示；
-r：recursive（递归）将参数中的目录和子目录下面的所有文件全部删除；
-v：verbose（详细）显示命令执行的详细信息；
4.范例：
[root@localhost ~]# rm -i a
rm: remove regular empty file `a'? y
[root@localhost ~]# ll
total 104
-rw-------. 1 root root 1645 Mar 16 2016 anaconda-ks.cfg
-rw-r--r--. 1 root root 0 Nov 11 2088 b
-rw-r--r--. 1 root root 50101 Mar 16 2016 install.log
-rw-r--r--. 1 root root 10608 Mar 16 2016 install.log.syslog
[root@localhost ~]# rm -f b
[root@localhost ~]# ll
total 104
-rw-------. 1 root root 1645 Mar 16 2016 anaconda-ks.cfg
-rw-r--r--. 1 root root 50101 Mar 16 2016 install.log
-rw-r--r--. 1 root root 10608 Mar 16 2016 install.log.syslog
[root@localhost ~]# rm -r a
rm: descend into directory `a'? y
rm: descend into directory `a/b'? y
rm: descend into directory `a/b/c'? y
rm: remove directory `a/b/c/d'? y
rm: remove directory `a/b/c'? y
rm: remove directory `a/b'? y
rm: remove directory `a'? y
[root@localhost ~]# rm -v a b c
rm: remove regular empty file `a'? y
removed `a'
rm: remove regular empty file `b'? y
removed `b'
rm: remove regular empty file `c'? y
removed `c'
