Bash usage examples

Contents

Navigating around
Files routines
Network routines
One-liners

Navigating around

# list sizes of files
$ ls -lah
# colored
$ ls -G
# count quantity of files inside folder
$ ls -1 | wc -l

Sizes

# check free disk space
$ df -h
# get folder size
$ du -hs
# get folders size inside another one
$ du -h --max-depth=1 some_folder

# search recursive by folders
$ grep -r "/api/Profile/active_home_devices" static/
# search by file content
$ grep -R 'GCModel' SemanticProcessor/
# find by filename
$ find ~ -name readme.txt

Zipping/unzipping

# unzip tar.gz file
$ tar -xvzf filename.tar.gz
# zip something
$ zip archive_name source_name
# unzip something
$ unzip archive_name

Files routines

Display part of the file

$ cat filename | less
$ tail -200 filename
$ head -200 filename
$ head -n 1000 filename | tail
# display to stdout
$ echo SOMETHING

Merge all files in folder to one

$ cat folder_path/* > new_file

Copy content of some text file

$ cat file_path | xclip -sel clip  # ubuntu
$ pbcopy < file_path  # mac

Encoding:

# get encoding of document
$ enca filename
# change encoding of doc
$ enconv filename

Network routines

Create an ssh key

ssh-keygen -t rsa -b 4096 -f ~/.ssh/key_name
cat ~/.ssh/key_name.pub | xclip -sel clip  # ubuntu
pbcopy < ~/.ssh/id_rsa.pub  # mac

Get list of all listened ports

$ sudo netstat -peanut

One-liners

Show running process by name with headers

$ ps aux | egrep "required_name|PID"

Execute output of some command(assume it in text file)

$ $(cat filename)

Check memory every 1 second

$ watch -n 1 free -m

Get the location of the executable link

$ readlink -f /usr/bin/java

Get dependencies

$ readelf -d some_exe

Find location of installed files

$ dpkg --listfiles libqt4-dev

Get CUDA version

$ dpkg -l | grep cuda

Remove range of folders starts with numbers

$ rm -r output/logs/{17..26}*

Send stdout to file and display it to the bash at the same time

$ ./some_file.sh | tee -a logs.txt

Handle docker containers

# all runing| second line| container name    | stop container by name
$ docker ps | sed -n 2p  | awk '{print $NF}' | xargs docker stop
# stop all running containers
$ docker ps | awk '{print $NF}' | tail -n +2 | xargs docker stop

Rename some folders by pattern

# find required folders  | split folder by '/' or '_' |
# based on split generate new name | call `mv` command with `system ()` flag
# note that splaces added in quotes
$ find . -type d -name "celeb*" |  awk -F '/|_' '{system ("mv " $0 " " $2"_mobile_"$3)}'