Interesting O & M programming questions

Interesting O & M programming questions

Use the for loop to create 10 html files in batch in the/oldboy directory with 10 random lowercase letters and a fixed string oldboy. The name is as follows:

 

coaolvajcq_oldboy.html qnvuxvicni_oldboy.html vioesjmcbu_oldboy.html gmkhrancxh_oldboy.html tmdjormaxr_oldboy.html wzewnojiwe_oldboy.html jdxexendbe_oldboy.html ugaywanjlm_oldboy.html xzzruhdzda_oldboy.html qcawgsrtkp_oldboy.html vfrphtqjpc_oldboy.html

 

 

#!/bin/bashletter=(`echo {a..z}`)function create_filename(){filename=`for i in $(seq 10)doecho -n ${letter[$(($RANDOM%24))]}done`_oldboy.html}for i in $(seq 10)docreate_filenametouch $filenamedone

Replace all oldboys in the above two file names with oldgirl (implemented using the for loop), and change html to uppercase.

 

 

#!/bin/bashfilelist=`ls | grep ".html$"`for i in $filelistdomv $i ${i%%_*}_oldgirl.HTMLdone

 

 

 

#!/bin/bashfilelist=`ls | grep ".html$"`for i in $filelistdonewfile=`echo $i | awk -F'_' '{print $1"_oldgirl.HTML"}'`mv $i $newfiledone

 

Create 10 SYSTEM account oldboy01-oldboy10 in batches and set the password (the password is a random 8-Bit String ).

 

#!/bin/bashfor i in `seq 10`doif [[ $i -lt 10 ]];thenuseradd oldboy0$i && echo `cat /dev/urandom | sed 's/[^a-zA-Z0-9]//g' | strings -n 8 | head -n 1` | passwd oldboy0$i --stdinelse useradd oldboy$i && echo `cat /dev/urandom | sed 's/[^a-zA-Z0-9]//g' | strings -n 8 | head -n 1` | passwd oldboy$i --stdinfidone

Write a script to determine the IP addresses of online users in the 10.0.0.0/24 network (there are many methods)

 

Single Process

 

#!/bin/bashfor i in `seq 2 255`doping 10.0.0.$i -c 1 1>/dev/null && echo 10.0.0.$i: live || echo 10.0.0.$i: deaddone

Multi-Process

 

 

#!/bin/bashtmp_fifofile="/tmp/$$.fifo"mkfifo $tmp_fifofileexec 6<>$tmp_fifofilerm -rf $tmp_fifofilethread=254for ((i=0;i<$thread;i++))doecho ""done >&6for ((i=1;i<254;i++))doread -u6        {        ping 10.0.0.$i -c 1 1>/dev/null && echo 10.0.0.$i: live || echo 10.0.0.$i: dead        echo "">&6        } &donewaitexec 6>&-exit 0

 

Bash for loop print the words with no more than 6 letters in the following sentence (Kunlun wanwei interview ).
I am oldboy teacher welcome to oldboy training class.

 

#!/bin/bashcontent="I am oldboy teacher welcome to oldboy training class."new_content=`echo $content | sed 's/\.//'`echo $new_contentarg=(`echo $new_content`)for i in ${arg[@]}doif [[ ${#i} -le 6 ]];thenecho $ifidone

 

It is known that the following string is the result after the RANDOM number variable md5sum | cut-c 1-8 is intercepted by RANDOM. Please crack the number of the RANDOM corresponding to the md5sum corresponding to these strings?

21029299

00205d1c

A3da1677

1f6d12dd

890684b

 

 

 

#!/bin/bashdeclare -a arrayfor i in $(seq 0 32767)doarray[$i]=`echo $i | md5sum | cut -c 1-8`donekeys=([0]=21029299 [1]=00205d1c [2]=a3da1677 [3]=1f6d12dd [4]=890684b)echo "number ------- md5sum"for key in ${keys[@]}dofor i in `seq 0 32767`doif [[ "${array[i]}" == "$key" ]];thenecho $i ------- $keyfidonedone