Very useful Cut command

I. Cut function-remove sections from each line of files (man cut)

Is responsible for cutting data in the file, andTake each row as a processing object, similar to SED, which is very useful in processing text data.

 

Ii. Command Format and locating methods

 
Cut option... [file]...
 

The cut command mainly accepts three positioning methods:

1, byte (bytes, in ascending order), with option-B

2, character (characters, if it is Chinese, it may be two bytes), use option-C

3, field (fields), with option-F

 

Iii. Examples

1. Extract 3rd bytes

 
Ll/dev/SDA *
 

 
BRW-RW ---- 1 root disk 8, 0 2012-03-20 13:13/dev/SDA
BRW-RW ---- 1 root disk 8, 1 2012-03-20 13:13/dev/sda1
BRW-RW ---- 1 root disk 8, 2 2012-03-20 13:13/dev/sda2
BRW-RW ---- 1 root disk 8, 3 2012-03-20 13:13/dev/sda3
 

 
Ll/dev/SDA * | cut-B 3
 

W
W
W
W

2. Extract multiple bytes

Ll/dev/SDA * | cut-B 1-8, 12
 

BRW-RW -- 1
BRW-RW -- 1
BRW-RW -- 1
BRW-RW -- 1

3. Other tips on Byte

1-

-3

-3, 3-

4. Extract characters

It is similar to byte-based, but if it is Chinese (multiple bytes), the extraction of byte may be garbled.

5. Extract the domain (this is the most useful)

It mainly specifies a delimiter (-d) and the domain (-F) to be extracted, as follows:

 
Ll/dev/SDA * | cut-d''-F1, 7-9
 

BRW-RW ----/dev/SDA
BRW-RW ----/dev/sda1
BRW-RW ----/dev/sda2
BRW-RW ----/dev/sda3

6. About
When the field is extracted, cut is distinguished by tabs (\ t) by default. to distinguish between tabs and spaces in text, run the following command:

 
Sed-N LFilename
 

 
Xin \ tjiang \ TLI \ tzong $
Xin \ tjiang \ TLI \ tzong $
$
 

Cut can only process text content separated by a single character. If multiple consecutive spaces (occupying multiple fields), it is more troublesome.