Several common text processing shell commands: Find, grep, Xargs, Sort, uniq, tr, cut, paste, WC, sed, awk

Content directory: Find file lookup grep text Search xargs command line parameter conversion sort sort Uniq eliminate duplicate rows with TR convert cut by column split text paste by column stitching text WC statistic lines and characters tool sed text substitution benefits The lines, words, and characters in the iteration file for the AWK Data flow processing tool

This article describes the most commonly used tools for using shell to process text under Linux:
Find, grep, Xargs, Sort, uniq, tr, cut, paste, WC, sed, awk;
The examples and parameters provided are the most common and practical;
The principle I use for Shell scripting is to write the command line, and try not to exceed 2 lines;
If you have more complex task requirements, consider Python; find File Lookup

Find txt and PDF files

  Find. \ (-name "*.txt"-o-name "*.pdf" \)-print

Find txt and PDF in a regular way

  Find. -regex  ". *\ (\.txt|\.pdf\) $"

-iregex: Ignores case-insensitive regular

Negative parameters
Find all non-txt text

   Find. ! -name "*.txt"-print

Specify Search Depth
Print out the current directory file (depth 1)

  Find. -maxdepth 1-type F  

Custom Search

Search By Type:

  Find. -type d-print  //Lists all catalogs only

-type f File/L Symbolic link

Search by Time:
-atime Access time (units are days, minutes are-amin, similar to the following)
-mtime modification Time (content modified)
-ctime change time (meta data or permission changes)
All files that have been visited in the last 7 days:

  Find. -atime 7-type F-print

Search by Size:
W Word k M G
Looking for files larger than 2k

  Find. -type f-size +2k

Find by Permission:

  Find. -type f-perm 644-print//Find all files with executable permissions

Find by User:

  Find. -type f-user weber-print//to find files owned by user Weber

follow-up action after finding

Delete:
Delete all SWP files in the current directory:

  Find. -type f-name "*.SWP"-delete

Execute action (Mighty exec)

  Find. -type f-user root-exec chown Weber {} \; Change ownership under current directory to Weber

Note: {} is a special string, for each matching file, {} will be replaced with the corresponding filename;
Eg: Copy all found files to another directory:

  Find. -type f-mtime +10-name "*.txt"-exec cp {} old \;

Combine multiple commands
Tips: If you need to execute multiple commands later, you can write multiple commands as a script. Then execute the script-exec the call;

  -exec./commands.sh {} \;

the delimiter of the-print

Use ' \ n ' as the delimiter for the file by default;
-print0 uses ' I ' as a delimiter for the file, so that you can search for files that contain spaces; grep text Search

grep match_patten File//default access matching row

Common parameters
-O outputs only matching lines of text vs-v output only lines that do not match
-C Statistics The number of times the file contains text

  Grep-c "text" filename

-N Print matching line numbers
-I ignores case when searching
-L print File name only

Recursive search of text in a multilevel directory (programmers search for code favorites):

  grep "Class". -r-n

Match multiple patterns

  Grep-e "Class"-E "vitural" file

The name of the grep output with the end character: (z)

  grep "Test" file*-lz| xargs-0 RM

xargs command line parameter conversions

Xargs can convert input data into command-line arguments for specific commands, which can be combined with many commands. such as grep, such as find;

Convert multiline output to single-line output
Cat file.txt| Xargs
\ n is a delimiter between multiple lines of text

Convert a single line to multiline output
Cat Single.txt | Xargs-n 3
-N: Specifies the number of fields to display per line xargs parameter Description

-D definition delimiter (the default is a multiple-line delimiter for \ n)
-n Specifies that the output is multiple lines
-I {} Specifies a replacement string that is replaced when the Xargs is extended, when multiple parameters are required for a command to be executed
eg

Cat File.txt | Xargs-i {}./command.sh-p {}-1

-0: Specify the input delimiter
Eg: statistics of the number of program lines

Find Source_dir