Shell

Objective How did grep get out?It's going to take us discovering, "g/re/p" see, that's it. "Global Regular expression print" ==> "globally finds the regular expression (RE) and prints the resulting row. ”The grep family consists of commands

#!/bin/bashcd= ' df-l |awk ' nr==3 {print $4} ' |awk ' BEGIN {fieldwidths= ' 2 1 "} ' {print '} 'If [$CD-ge 20];thenecho " hard disk space is full and cannot be backed up " | Mutt-s " backup alarm, please replace the hard drive in time " [Email

Transferred from: http://www.cppblog.com/zhangyq/archive/2010/10/08/127915.html1.txt content:File contentAabbccAbcdefgHilkdifdfdfMmmmmmmmEeeeeeeeeeeeeeComment Part 2>>>DdeeffSED-E ": Begin; />>/{/>>>/! { $! {N; b begin}; }; s/>>//; };" 1.txtFile

For C in a B C D E F g;do echo $c; Done sequentially outputFor C in a B C D E F g;do tar czvf install.log. $c. tar.gz Install.log; DoneFor C in {a.. g}; do echo $c; Done the same as aboveSeq 1 10 columns of numbersFor i in {1..10}; do echo $i;

Write a script that calculates all the odd and all the even numbers within 100 and displays them separately#! /bin/bashSum1=0For i in ' SEQ 1 2 100 'Dosum1=$[$sum 1+ $i]Doneecho $sum 1Sum2=0For j in ' SEQ 2 2 100 'Dosum2=$[$sum $j]DoneEcho $sum

1:declare commandshell Default is String typeIf subtraction is required, it needs to be defined as an integral typeDECLARE command: Change the default variable type Decalre [+/-] [option] Variable name-set type properties for variables+ Cancel

The shell practice of Linux Learning 1. Describe the operation principle of shell program (can be attached with necessary graphic instructions);2, summarize all the knowledge points involved in shell programming (such as: variables, grammar,

Shell Common Command Summary1 ls command: List filesLs-la list all files and folders in the current directoryLS A * lists all files starting with the A letter in the current directory Ls-l *.txt Lists all files with the suffix txt in the current

#!/bin/Sh#today= ' Date +%y%m%d ' year= ' echo $ '1|cut-c1-4' MONTH= ' echo $ '1|cut-c5-6' Day= ' echo $ '1|cut-c7-8' time= $YEAR-$MONTH-$DAY #echo ' Date-D"$TIME-2 Day"+%y-%m-%d ' URL="/home/work/webdata/logs/focusapi_access_log.$1"#昨天的日期 #yes_dt= '

When the shell executes a command, it returns a return value that is saved in the shell variable $? In When $? = = 0 o'clock, indicating successful execution; = = 1 o'clock, which indicates that the execution failed.    www.2cto.com   Sometimes the

Shell Introductionbash programming, then start with the programming, What is the program first? Personal words Explanation: program is the process of processing data. So, The program design consists of : program = data structure +

Because I usually write some small experimental script, every time to write author,description and so very troublesome, then wrote such a script can create their own small script, code as follows, pure personal original, relatively rough, big God

Shell Introduction The shell is a programming language interpreter, which interprets commands entered from the keyboard, and also explains the sequence of commands stored in the script, which is a file containing a series of commands, and

　　#!/bin/bashif [$#-ne 1];then echo "usage:$0 filename"; Exit-1fifilename=$1egrep-o "\b[[:alpha:]]+\b" $filename | awk ' {count[$0]++}end{printf ("%-14s%s\n", "Word", "Count"), for (Ind in count) {printf ("%-14s%d\n", Ind,count[ind]);}}

List The 10 shells you use mostHistory | awk ' {a[$2]++}end{for (i in a) {print a[i] "i}} ' | Sort-rn | HeadHistory | awk ' {a[$4]++}end{for (i in a) {print a[$i] " " i}} ' | sort-rn | headgrep-v "#". Bash_history |awk ' {++a[$1]}end{for

character meaning * Match 0 or more characters ? Match any one character [list] Match any single character in the list [!list] Matches a character other

1. Describe the operation principle of shell program (can be attached with necessary graphic instructions);   Span style= " font-size:12px;">shell is a special program that is officially defined as the interface to the kernel and is

Requirement Description: The string in the document is counted and sorted (from large to small), the test.txt content of the first 2 records is displayed as follows: A 12332a 2323a 234234b 232c 23432c 34 statistics and Sorting methods:

First, an array overviewArrays: Data StructuresData series, continuous multiple data, can be used to get related elements of the indexDeclaring an array:declare-e arraynameInitialization assignment:arrayname= ("STRING1" "STRING2" ... )Arrayname=

Multi-thread Linux Shell script and linuxshell In bash, we run (&) in the background to implement multithreading. for((i=1;i We have added {} & so that the execution in {} can be performed in the background. The above is equivalent to executing