Shell file processing Tools

vim/etc/resolve.conf View DNS
6.shell script Commands
1.diff
Diff file File compares the differences of two files
-C Displays the surrounding rows
-U generates patches in a uniform output format
-R comparison of files in two directories
Pattch file File.path patch
-B Back up the original file
2.grep
grep Key Character File | Directory finds rows in a file or directory that contain keywords
Grep-i ignoring case
-n Displays the keyword in the row
-C Displays the number of rows for filtered results
-V Reverse Filter
-e "keyword 1| keyword 2" filters multiple keywords
-R directory to find files in the directory that contain keywords
Note: The ^ keyword starts with a keyword
Keyword $ ends with keyword
^root start with Root
root$ End With Root
3.cut
Cut intercept characters
Cut-d delimiter Specifies delimiter
Cut-f 1,7 Displays the specified column
CUT-C display of specified characters
Cut-d ""-F 10 intercepts the space after the tenth column to the next delimiter space between the contents
4.sort sorting
Sort
-N Pure Digit sort
-U Remove Duplicate
|uniq-c Remove duplicates and count repetitions
-T Specify delimiter
-k Specifies the column
SORT-T:-K 2 File-nu
5.uniq
Sort File | Uniq-c remove excess and count repetitions
-D Show Extra rows
-U displays unique rows
6.tr
Tr ' A-Z ' A-z ' file
Sed ' s/original character/replacement character/g ' file
Sed-e ' policy 1 '-e ' policy 2 ' file multiple policies with-E
Sed-i file outputs the transferred files to the specified file
Sed ' 3,5s/original character/replace character/' file
SED xd mask specified line
Sed XP replicates the specified line
Sed-n XP displays only the specified lines
Script
#!/bin/bash
max=$ (Wc-l $ | cut-d ""-F 1)
For NUM in $ (seq $MAX)
Do
username=$ (Sed-n ${num}p$1)
passwd=$ (sed in ${num}p)
Useradd $USERNAME
echo $PASSWD | passwd--STDIN$USERNAMR
Done

7.awk Data processing tool that divides a line into segments for processing, with the smallest number of processing units in a field

awk ' condition type 1{action 1} condition type 2{action 2} ... ' filename
[Email protected] ~]# Last-n 5
Kiosk pts/0:0 Wed Nov 9 19:46 still logged in
Kiosk pts/0:0 Wed Nov 9 18:57-19:46 (00:48)
kiosk:0:0 Wed Nov 9 18:57 still logged in
Reboot system boot 3.10.0-327.el7.x Thu Nov 10 02:56-19:59 ( -6:-57)
kiosk:0:0 Wed Nov 9 17:55-17:55 (00:00)

Wtmp begins Wed Sep 28 00:38:05 2016
[[email protected] ~]# Last-n 5 | awk ' {print $ ' \ t ' $} '
kiosk:0
kiosk:0
kiosk:0
Reboot boot
kiosk:0

$ A represents a whole row of data
Built-in variables
NF total number of fields per row ($)
NR current awk is dealing with the first few rows of data
FS Current separator character, default is space key
[[email protected] ~]# Last-n 5 | awk ' {print $ ' lines: ' NR ' \tcolumes: ' NF} '
Kiosklines:1 columes:10
Kiosklines:2 columes:10
Kiosklines:3 columes:10
Rebootlines:4 columes:11
Kiosklines:5 columes:10
Lines:6 columes:0
Wtmplines:7 columes:7
Condition type
[Email protected] ~]# CAT/ETC/PASSWD | awk ' {fs= ': '} $3<10 {print ' \ t ' $ $} '
Root:x:0:0:root:/root:/bin/bash
Bin 1
Daemon 2
ADM 3
LP 4
Sync 5
Shutdown 6
Halt 7
Mail 8
The first line or the default space bar is the delimiter, want to start from the first line in the delimiter {fs= ":"} before the BEGIN keyword in addition to the end
[Email protected] ~]# CAT/ETC/PASSWD | awk ' begin{fs= ': "} $3<10 {print$1" \ T "$} '
Root 0
Bin 1
Daemon 2
ADM 3
LP 4
Sync 5
Shutdown 6
Halt 7
Mail 8
The awk command calculates
Name 1st 2nd 3th
Zed 12321 34123 41234
Timo 23413 34124 35213
lol 34223 12441 22341
Cat File | awk ' nr==1{printf '%10s%10s%10s%10s%10s\n ", $1,$2,$3,$4," Total "}nr>=2{total=$2+$3+$4 printf"%10d%10d%10d%10d% 10.2f\n,$1,$2,$3,$4,total} '

Shell file processing Tools