I have marked with a * (not apparent in the MD preview) those which I think are absolutely essential Items for each section are sorted by oldest to newest.

Come back soon for more!

• In bash, 'ctrl-r' searches your command history as you type

• Input from the commandline as if it were a file by replacing 'command < file.in' with 'command <<< "some input text"'
• '^' is a sed-like operator to replace chars from last command 'ls docs; ^docs^web^' is equal to 'ls web'. The second argument can be empty.

• '!!:n' selects the nth argument of the last command, and '!$' the last arg 'ls file1 file2 file3; cat !!:1-2' shows all files and cats only 1 and 2

• More in-line substitutions: http://tiny.cc/ecv0cw http://tiny.cc/8zbltw
• 'nohup ./long_script &' to leave stuff in background even if you logout
• 'cd -' change to the previous directory you were working on
• 'ctrl-x ctrl-e' opens an editor to work with long or complex command lines

• Use traps for cleaning up bash scripts on exit http://tiny.cc/traps
• 'shopt -s cdspell' automatically fixes your 'cd folder' spelling mistakes
• Add 'set editing-mode vi' in your ~/.inputrc to use the vi keybindings for bash and all readline-enabled applications (python, mysql, etc)

• function lt() { ls -ltrsa "$@" | tail; }
• function psgrep() { ps axuf | grep -v grep | grep "$@" -i --color=auto; }
• function fname() { find . -iname "$@"; }
• function remove_lines_from() { grep -F -x -v -f $2 $1; } removes lines from $1 if they appear in $2
• alias pp="ps axuf | pager"
• alias sum="xargs | tr ' ' '+' | bc" ## Usage: echo 1 2 3 | sum
• function mcd() { mkdir $1 && cd $1; }

• ':set spell' activates vim spellchecker. Use ']s' and '[s' to move between mistakes, 'zg' adds to the dictionary, 'z=' suggests correctly spelled words
• check my .vimrc http://tiny.cc/qxzktw and here http://tiny.cc/kzzktw for more

• 'htop' instead of 'top'

• 'ranger' is a nice console file manager for vi fans
• Use 'apt-file' to see which package provides that file you're missing
• 'dict' is a commandline dictionary
• Learn to use 'find' and 'locate' to look for files
• Compile your own version of 'screen' from the git sources. Most versions have a slow scrolling on a vertical split or even no vertical split at all

• 'trash-cli' sends files to the trash instead of deleting them forever. Be very careful with 'rm' or maybe make a wrapper to avoid deleting '' by accident (e.g. you want to type 'rm tmp' but type 'rm tmp *')

• 'file' gives information about a file, as image dimensions or text encoding
• 'sort | uniq' to check for duplicate lines
• 'echo start_backup.sh | at midnight' starts a command at the specified time
• Pipe any command over 'column -t' to nicely align the columns

• Google 'magic sysrq' to bring a Linux machine back from the dead

• 'diff --side-by-side fileA.txt fileB.txt | pager' to see a nice diff

• 'j.py' http://tiny.cc/62qjow remembers your most used folders and is an incredible substitute to browse directories by name instead of 'cd'

• 'dropbox_uploader.sh' http://tiny.cc/o2qjow is a fantastic solution to upload by commandline via Dropbox's API if you can't use the official client
• learn to use 'pushd' to save time navigating folders (j.py is better though)
• if you liked the 'psgrep' alias, check 'pgrep' as it is far more powerful

• never run 'chmod o+x * -R', capitalize the X to avoid executable files. If you want only executable folders: 'find . -type d -exec chmod g+x {} ;'

• 'xargs' gets its input from a pipe and runs some command for each argument

• run jobs in parallel easily: 'ls *.png | parallel -j4 convert {} {.}.jpg'

• grep has a '-c' switch that counts occurences. Don't pipe grep to 'wc -l'.

• Don't know where to start? SMB is usually better than NFS for most cases.
• If you use 'sshfs_mount' and suffer from disconnects, use '-o reconnect,workaround=truncate:rename'
• 'python -m SimpleHTTPServer 8080' shares all the files in the current folder over HTTP, port 8080
• 'ssh -R 12345:localhost:22 server.com "sleep 1000; exit"' forwards server.com's port 12345 to your local ssh port, even if you machine is not externally visible on the net. Now you can 'ssh localhost -p 12345' from server.com and you will log into your machine. 'sleep' avoids getting kicked out from server.com for inactivity

• Read on 'ssh-agent' to strenghten your ssh connections using private keys, while avoiding typing passwords every time you ssh.

• 'socat TCP4-LISTEN:1234,fork TCP4:192.168.1.1:22' forwards your port 1234 to another machine's port 22. Very useful for quick NAT redirection.
• Some tools to monitor network connections and bandwith: 'lsof -i' monitors network connections in real time 'iftop' shows bandwith usage per connection 'nethogs' shows the bandwith usage per process

• Use this trick on .ssh/config to directly access 'host2' which is on a private network, and must be accessed by ssh-ing into 'host1' first Host host2 ProxyCommand ssh -T host1 'nc %h %p' HostName host2
• Pipe a compressed file over ssh to avoid creating large temporary .tgz files 'tar cz folder/ | ssh server "tar xz"' or even better, use 'rsync'
• ssmtp can use a Gmail account as SMTP and send emails from the command line. 'echo "Hello, User!" | mail [email protected]' ## Thanks to Adam Ziaja. Configure your /etc/ssmtp/ssmtp.conf: root=E-MAIL mailhub=smtp.gmail.com:587 rewriteDomain= hostname=smtp.gmail.com:587 UseSTARTTLS=YES UseTLS=YES AuthUser=E-MAIL AuthPass=PASSWORD AuthMethod=LOGIN FromLineOverride=YES

(CC) by-nc, Carlos Fenollosa [email protected]

Retrieved from http://cfenollosa.com/misc/tricks.txt

Last modified: Fri Feb 28 07:18:39 CET 2014