(1)touchThe command is used to modify the access time and modification time of a file. If no time is specified, change the file time attribute to the current time.
When the specified file does not exist, the touch command becomes to create the file.
grammar:
touch [-acm] [-d STRING-time] [-r reference-file] [-t [[CC]YY]MMDDhhmm[.ss]]
Option description:
-a: Only modify access time;
-c: If the specified file does not exist, the file will not be created;
-d STRING-time: Use the time in string format to specify the modified value of the time attribute;
-m: Only modify the modification time of the specified file;
-r reference-file: Change the time attribute of the specified file to the same value as the reference-file time attribute;
-t [[CC]YY]MMDDhhmm[.ss]: Use the time format [[CC]YY]MMDDhhmm[.ss] to specify the modified value of the time attribute;
Create a file that does not exist
Order:
touch
If it does not exist, no file is created
[root@localhost test]# touch -c ##If there is no change file, it won't be created
(2) > is redirected to a file.>>It is to add content to the file. Both commands create a file if the file does not exist
echo "test content" >
## Using the redirection ">" function, writing the output result of a command into a file will overwrite the original file content. If the specified file does not exist, it will be created.
echo "test content two" >>
## Append the output result of a directive to a file, and the original file content will not be overwritten.
(3)vi/vim
vim is an upgraded version of vi, with more commands and stronger functions
Create a file
vi
vim
To exit in vi/vim
Press the Esc key first, then press the following
:wq or:x �
:q
:q!
Vim usage:
1. First, directly enter the general mode: delete, copy and paste commands
x,X
nx(n represents number) �
dd �
D
ndd(n represents number)
d1G
dG
yy
y1G Copy all data from the line where the cursor is located to the first line
yG Copy all data from the line where the cursor is located to the last line
ynj(n represents number) Copy the line where the cursor is located down to n+1 line
dnj(n represents number)
p,P
J
u �
2. Press the i key to enter the editing mode command, press the Esc key to exit, enter the general mode
i,I
a,A a is the input text inserted at the next character where the cursor is located, and A is the input text inserted at the next character on the last character on the line where the cursor is located.
o,O o Insert characters at the beginning of the next line of the cursor, O Insert characters at the beginning of the previous line of the cursor
r,R
Esc
3. Press the: key in general mode to enter command mode
h �
j
k
l
Ctrl+f
Ctrl+b
Ctrl+d
Ctrl+u
+ �
- �
n spaces (n represents numbers) �
0(number 0) move the cursor to the first character of the current line (can be null characters, please note that it is different from -)
$ �
H
M �
L �
G �
nG(n represents number) The cursor moves to the first non-empty character on line n of the article
n �
/word
?word
:s/word1/word2/g Find word1 in the current line of the cursor and replace it with word2
:n1,n2s/word1/word2/g Look for word1 between line n1 and line n2 and replace it with word2
:%s/word1/word2/g Look for word1 in the entire article and replace it with word2
:w
:w [filename] Save the edited data to another file on the hard disk
:r [filename] When editing the data, read the data in another file, that is, add the contents in the filename file to the next line where the cursor is located
:wq or:x �
:q
:q! �
:set nu Show line number
:set nonu Cancel line number
:n1,n2 w [filename] Save the contents of lines n1 to n2 to a file named filename