1, Command introduction
The command cut can be used to split the string and display the content of the specified range. The text content can be displayed according to the specified byte range, character range and split field range. You can also merge the contents of multiple files.
2, Common options
| option | explain |
|---|---|
| -b | Displays the characters in the specified byte range in the line in bytes |
| -c | Displays the characters in the specified character range in the line in character units |
| -d | Specifies the field separator. The default field separator is TAB. The field separator must be enclosed in quotation marks, either single quotation marks or double quotation marks. Spaces are allowed between the separator and option - d |
| -f | Displays the contents of the specified field |
| -n | Used with the - b option to not split multi byte characters |
| --output-delimiter=<STRING> | Specify the field separator of the output. No space is allowed between the separator and the option. The separator can be without quotation marks, but if the specified separator is a special symbol, it must be quoted |
| --help | Displays help information for the command |
| --version | Displays the version information of the instruction |
| --complement | It is used to exclude the character content in the specified range. The actual effect is inconsistent with the meaning of the word complex. It can only be considered that the foreigner's understanding is against the sky! |
3, Command example
Displays the contents of the specified file according to the specified byte range
File text Txt is as follows:
[root@htlwk0001host test]# cat text.txt hello shell world! dfdskklllllf dfsfdsf shell world sdffdsfdsfd dfsfdfdsfds fsdfdsfdsfdsf fdsfdsfdsfd
Display file text Txt contents of the 1st to 8th bytes of each line:
[root@htlwk0001host test]# cut -b1-8 text.txt hello sh dfdskkll dfsfdsf shell wo sdffdsfd dfsfdfds fsdfdsfd fdsfdsfd
Note: - b indicates that the characters in the specified byte range in the line are displayed in bytes
Display file text Txt characters in the 1st byte and 8th byte of each line:
[root@htlwk0001host test]# cut -b1,8 text.txt hh dl d so sd ds fd fd
Specify the field separator to display the contents of the specified field
In fact, it is a user-defined separator to segment the content of each line of text, and then select the content of some fields after segmentation for display.
[root@linuxcool ~]# cat student2.txt No;Name;Mark;Percent 01;tom;69;91 02;jack;71;87 03;alex;68;98
Specify a semicolon; As a separator, display the contents of the second field:
[root@linuxcool ~]# cut -f2 -d";" student2.txt Name tom jack alex
Note: the field separator can be without quotation marks, and spaces are allowed between the separator and option - d.
Displays the contents of the specified field
The default field separator is TAB, so each field of text content has been separated by TAB. You can directly use the option - f to display the content of the specified field:
[root@linuxcool ~]# cat student.txt No Name Mark Percent 01 tom 69 91 02 jack 71 87 03 alex 68 98
Use the - f option to display the contents of the second field:
[root@linuxcool ~]# cut -f 2 student.txt Name tom jack alex
Display the contents of the 2nd and 3rd fields:
[root@localhost text]# cut -f2,3 test.txt Name Mark tom 69 jack 71 alex 68
Displays the contents of the specified file according to the specified character range
File test Txt is as follows:
[root@linuxcool ~]# cat test.txt abcdefghijklmnopqrstuvwxyz abcdefghijklmnopqrstuvwxyz abcdefghijklmnopqrstuvwxyz abcdefghijklmnopqrstuvwxyz abcdefghijklmnopqrstuvwxyz
Display the contents of characters 1 to 3:
[root@linuxcool ~]# cut -c1-3 test.txt abc abc abc abc abc
Display the first 2 characters of each line:
[root@linuxcool ~]# cut -c-2 test.txt ab ab ab ab ab
Display content from the beginning to the end of the fifth character:
[root@linuxcool ~]# cut -c5- test.txt efghijklmnopqrstuvwxyz efghijklmnopqrstuvwxyz efghijklmnopqrstuvwxyz efghijklmnopqrstuvwxyz efghijklmnopqrstuvwxyz
explain:
| Range expression | explain |
|---|---|
| n- | From the nth byte, character, field to the end |
| n-m | From the nth byte, character and field to the m-th byte, character and segment, including n and m |
| -m | From the 1st byte, character, field to the m-th byte, character, field |
Displays the contents of fields other than the specified field
You can use the option -- complex to extract columns other than the specified fields, that is, print the contents of columns other than the second column:
[root@linuxcool ~]# cut -f2 --complement student.txt No Mark Percent 01 69 91 02 71 87 03 68 98
Splits the fields in the output content with the specified output separator
You can use the option -- output delimiter to specify the field separator when outputting content. For example, specify the field separator that matches # as output, as shown below:
[root@htlwk0001host test]# cut -d';' -f2,4 --output-delimiter='#' text2.txt Name#Percent tom#91 jack#87 alex#98
explain:
-d';' Indicates the semicolon in the input data stream; The text content of each line is divided as a field separator, and -- output delimiter = '#' indicates that the content is displayed with # as a field separator when the content is output.
Merge the contents of multiple files
Merge the contents of files f1 and f2, and then put the merged contents into file f3 by overwriting the output redirection > as follows:
[root@htlwk0001host test]# cut f1 f2 > f3