Very important basic Commands Three Musketeers plus find

Find-type: Search by file type

-name: Search by file name

！ Take counter

SED command combat:

Sed-n "2p" oldboy.txt print the second line

Sed-n "1,2p" Oldboy.txt print line first to second

Replace DDD with Oldboy print: sed ' s#ddd#oldboy#g ' oldboy.txt

Change the content ddd to Oldboy and print: Sed-i ' s#ddd#oldboy#g ' oldboy.txt

Basic Regular Expressions: Some special symbols represent some special functions and functional definitions.

Sed-i ' s# (regular match available) #\1#g ' Oldboy.txt

. Single arbitrary character

* Repeat any of the preceding 0 or more characters

. * matches any character

Enclose the result in parentheses in the preceding regular match, followed by a \1 representation.

$ A indicates the entire row

Example: Sed-r ' s# (. *) Fff#\1#g ' oldboy.txt matches the characters in front of FFF and outputs

Sed-r ' s# (. *) (. *) #\1 \2#g ' oldboy.txt matches characters before and after spaces and outputs

awk Command Combat:

awk ' {print '} ' Oldboy.txt takes the first column

awk ' {print $ oldboy.txt} ' takes first, two columns

awk ' {print $NF} ' Oldboy.txt takes the last column

Awk-f "Specify delimiter" ' {print $NF} ' Oldboy.txt

Cat-n Display the line number of the file

awk ' {nr>20&&nr<26} print $/etc/passwd prints 21-25 lines

grep command Combat:

grep***** (good at filters) separate the desired or unwanted (the default whole line)

-V Exclusion

-I is case insensitive

-E Filter Multiple strings

-O outputs precisely matched characters without

-N Line number

Linux Three Musketeers old three

-B In addition to displaying a matching row, and displaying the NUM lines before the line

-a displays a matching row and Num lines after that line

-c Displays the NUM row before and after the line, except for a matching row

grep "string"-B 1.txt

--color=auto to match the string to a color

grep 3306/etc/services

grep--color=auto 3306/etc/services

Very important basic Commands Three Musketeers plus find