Linux Common commands

1. Convert lowercase letters to uppercase

echo "ABcD" |tr ' A-Z ' ' A-Z '

2. Uppercase letter Conversion lowercase letters

echo "ABcD" |tr ' A-Z ' ' A-Z '

3. Current Script path

basepath=$ (CD ' DirName $ '; pwd)

For detailed explanations, please see http://www.cnblogs.com/FlyFive/p/3640267.html

4. Common Date Variables

Date + '%y%m%d%h%m%s '

The output format is: 20161027090005

Date + '%y-%m-%d%h:%m:%s '

The output format is: 2016-10-27 09:00:05

5. Sed common commands

Delete the line that matches test

Sed-i '/test/d '/tmp/test.txt

Modify the contents of the/tmp/test.txt test to Test1

Sed-i ' s/test/test1/g '/tmp/test.txt

If you encounter special characters, replace/substitute # or other characters. For example: Sed-i ' s#test#test1#g '/tmp/test.txt

6, Row to column

Execute command: Cat/tmp/test.txt

Output:

A b C

Execute command:

For Parm in $ (cat/tmp/test.txt)

Do

Echo $parm

Done

Output Result:

A

B

C

7. List of career change

Execute command: Cat/tmp/test.txt

Output:

A

B

C

Execute command: cat/tmp/test.txt|xargs-r

Output:

A b C

Linux Common commands