Details of Linux basic command mktemp

mktemp

Create temporary files or directories in a safe way. This command applies to: RedHat, RHEL, Ubuntu, CentOS, SUSE, openSUSE, Fedora.

1, grammar,

mktemp [Option] [TEMPLATE]

2. List of options

选项	说明
--version	显示命令版本信息
--help	显示帮助信息
-d | --directory	创建目录
-u | --dry-run	不要创建任何东西，只要打印1个名字（不安全）
-q | --quiet	发生错误的时候不显示提示信息
--suffix=SUFF	附加SUFF到模板中。SUFF不能包含斜杠。如果模板不以X结尾，则使用此选项。
--tmpdir[=dir]	指定临时文件的路径，如果tmpdir后面没有路径，那么使用变量$TMPDIR；如果这个变量也没指定，那么临时文件创建在/tmp目录下。使用此选项，模板不能是绝对名称。与“-t“不同，模板可能包含斜杠，但mktemp只创建最终组件
-p DIR	使用DIR作为前缀
-t	将模板解释为1个相对于目录$TMPDIR(如果设置)的单个文件名组件；否则通过-p指定的目录；或者使用/tmp（-t已经弃用）
TEMPLATE	临时文件名，名字中必须包含至少3个字母X。如果没有指定，那么默认是tmp.XXXXXXXXXX

3, the instance,

1) Create temporary files

[root@localhost weijie]# mktemp wj123.XXXX // Name contains 4 a X
wj123.kpET
You have new mail in /var/spool/mail/root
[root@localhost weijie]# mktemp wj123.XXXXXX // Name contains 6 a X
wj123.oH2o4P
[root@localhost weijie]# ls
1.c wj123.kpET wj123.oH2o4P

2) Create a temporary directory

[root@localhost weijie]# mktemp -d wjtp  // Not in the name X

mktemp: There is too little X in the template "wjtp"

[root@localhost weijie]# mktemp -d wjtpxxx // Not in the name X You can see here X It has to be uppercase 
mktemp:  The template "wjtpxxx"  In the X  Too little 
[root@localhost weijie]# mktemp -d wjtpXXX // Creating a successful 
wjtpflR
 [root@localhost weijie]# ls -l

The total amount of 4

-rw-r--r-- 1 root root 0 9 month  7 09:11 1.c
-rw------- 1 root root 0 9 month  7 14:47 wj123.kpET
-rw------- 1 root root 0 9 month  7 14:47 wj123.oH2o4P
drwx------ 2 root root 4096 9 month  7 14:50 wjtpflR

3) Create temporary files in /tmp

[root@localhost weijie]# mktemp --tmpdir wj234.XXX  //tmpdir No path is specified at tmp create 
/tmp/wj234.BNy
You have new mail in /var/spool/mail/root

4) Create a temporary directory under the specified directory

[root@localhost weijie]# mktemp --tmpdir=/weijie wj234.XXX // in tmpdir Created under the specified path 
/weijie/wj234.q1C
[root@localhost weijie]# ls
1.c wj123.kpET wj123.oH2o4P wj234.q1C wjtpflR

5) Create with option -ES48en

[root@localhost weijie]# mktemp -u wj123.XXXXXX  // use -u options 
wj123.dSgIKl
[root@localhost weijie]#ls     // You cannot see the temporary file because it was not created 
1.c wj123.kpET wj123.oH2o4P wj234.q1C wjtpflR

Added: linux base command

1. Basic command

ls: Lists the files or directories in the current directory

2. ls-a: List all files and directories under the current directory (including hidden files)

3. ls-l: Display file details (long format information view), equivalent to ll

ls-hl: Displays file details and file size
ls-al: Lists the details of all files and directories in the current directory
ls-dl: Displays details of the current file itself

4. cat command: View file information (only view files)

[root @com ~]# cat /etc/passwd: View all user information
[root @com ~]# cat /etc/group: View all user group information

Note: For every user created in Linux, a corresponding user group is automatically generated.

cd command: switch directories

 [root@com ~]# cd /etc  : Switch to the root directory etc directory 
  pwd : Displays the directory of the current file 
  whoami: View the current user 
    [root@com etc]# whoami : View the current user is root The user 
    root 

6, / : represents the user's root directory

Home directory (host directory)

1) Home directory of administrator user:

  [root@com ~]# pwd
    /root

2) Home directory of ordinary users:

[java17@com ~]$ pwd
    /home/java17

7. Switch user command: su - user name

1) Switch to normal user

[root@localhost weijie]# mktemp -d wjtp  // Not in the name X

0

2) Switch to root administrator user

[root@localhost weijie]# mktemp -d wjtp  // Not in the name X

1

8. Shut down, restart and clear the screen

Turn off: halt, init 0, shutdown now
Restart: reboot, init6
Clear screen: clear, Ctrl+l

conclusion