1.平级切换目录eg：从/a/b/c/kk 切换到 /a/b/f/kk
cd ${PWD/c/f} #主要是shell的字符串替换
2.随机生成一个ip
echo $((RANDOM%256)).$((RANDOM%256)).$((RANDOM%256)).$((RANDOM%256)...
1.平级切换目录eg：从/a/b/c/kk 切换到 /a/b/f/kk
cd ${PWD/c/f} #主要是shell的字符串替换
2.随机生成一个ip
echo $((RANDOM%256)).$((RANDOM%256)).$((RANDOM%256)).$((RANDOM%256))
3.this will fill your shell with random data, parts of it highlighted （偷懒专用）
cat /dev/urandom | hexdump -C |grep --color=yes -E "(ca|fe|3d|42|e1|b3|ae|f8)" | perl -MTime::HiRes -pne "Time::HiRes::usleep(rand()*1000000)"
4.Selecting a random file/folder of a folder random file from files in directory
ls -1 | shuf -n 1
5.随机生成合法的mac地址
python -c "from itertools import imap; from random import randint; print ':'.join(['%02x'%x for x in imap(lambda x:randint(0,255), range(6))])"
for i in {1..6}; do printf "%0.2X:" $(($RANDOM % 0x100 )); done | sed 's/:$/\n/'
for i in {1..6}; do printf "%0.2X:" $[ $RANDOM % 0x100 ]; done | sed 's/:$/\n/'
h=0123456789ABCDEF;for c in {1..12};do echo -n ${h:$(($RANDOM%16)):1};if [[ $((c%2)) = 0 && $c != 12 ]];then echo -n :;fi;done;echo
6.将一个字符串split 成数组：awk:echo ‘a s d a da daa’ |awk '{split($0,arr);print arr[1]}'
herestring: read -a ARR <<< "a s d a da daa";echo ${ARR[2]}
7
.让自己的终端显示时间 export PS1="(\@) $PS1"
8.Create date-based tgz of current dir, runs in the background, Here is the full alias
alias tarred='( ( D=`builtin pwd`; F=$(date +$HOME/`sed "s,[/ ],#,g" <<< ${D/${HOME}/}`#-%F.tgz); tar --ignore-failed-read --transform "s,^${D%/*},`date +${D%/*}.%F`,S" -czPf "$"F "$D" &>/dev/null ) & )'
9.显示bash 256种颜色所对应的数值for i in {0..255}; do echo -e "\e[38;05;${i}m${i}"; done | column -c 80 -s ' '; echo -e "\e[m"
10.模拟黑客帝国的字符屏幕 :)[Blue Matrix]while [ 1 -lt 2 ]; do i=0; COL=$((RANDOM%$(tput cols)));ROW=$((RANDOM%$(tput cols)));while [ $i -lt $COL ]; do tput cup $i $ROW;echo -e "\033[1;34m" $(cat /dev/urandom | head -1 | cut -c1-1) 2>/dev/null ; i=$(expr $i + 1); done; done
11.快速查阅date 日期表示帮助文档
alias dateh='date --help|sed "/^ *%a/,/^ *%Z/!d;y/_/!/;s/^ *%\([:a-z]\+\) \+/\1_/gI;s/%/#/g;s/^\([a-y]\|[z:]\+\)_/%%\1_%\1_/I"|while read L;do date "+${L}"|sed y/!#/%%/;done|column -ts_'
12.迅速搭建webserver (在文件传输方面能派上用场，wget curl)
python -m SimpleHTTPServer
Serve current directory tree at http://$HOSTNAME:8000/
13.This command will start a simple SMTP server listening on port 1025 of localhost. This server simply prints to standard output all email headers and the email body.
python -m smtpd -n -c DebuggingServer localhost:1025
