Linux Commands

1. Show Desktop
Control + Win + D
2. Lock Desktop
Control + Alt + L
3. Delete current command quickly
Control + U
4. List file size (Directory)
du -sh /path
5. List installed packages
sudo apt list –installed | grep “name”
6. Check information without opening file
cat xxx.txt | grep “name”
tail xxx.txt
7. Ubuntu install deb file

// sudo apt install ./xxx.deb
sudo dpkg -i ./xxx.deb
sudo install -f

8. tmux
Control + A Then (Up, Down, Left, Right) switch windows (Default tmux is Control + B)
9. TensorBoard

tensorboard --logdir=/path/to/logdir

10. SCP

# 1. Download file through server to client:
scp username1@hostname1:/path/to/file /local/path/to/file
# 2. Upload file from client to server:
scp /path/to/local/file username@hostname:/path/to/remote/file
# 3. Upload folders:
scp -r /source /destination

11. virtualenv

# Create:
virtualenv /path/to/venvs/

# Activate:
source /path/to/venvs/name/bin/activate

# For Python 3:
sudo apt-get install python3-venv
python3 -m venv /path/to/new/virtual/environment

12. Git to Gerrit

git pull
git add ...
git commit -m "..."
git pull --rebase
git push origin HEAD:refs/for/master

13. Fast Copy and Paste:
Select the text you want to copy, then go to the place where you want to copy to and press the scroll wheel of the mouse.

14. Check file / folder size du command.

Size of a directory:
$ du -sh /tmp
Size of a file:
$ du -h /tmp/xyz

15. Download file using SFTP

# Connection:
sftp username@remote_hostname_or_IP

# Download:
get (-r) some_remote_file

# Upload:
put (-r) some_local_file

# OR download directly:
sftp username@remote_address:/path/to/file/some_remote_file

16. Download files from URL in terminal

wget "http://......"
# or
wget -o /path/to/file "http://......"

17. Update specific package in Ubuntu:

apt-get install --only-upgrade <packagename>

18. Compress and extract files:

Compress a folder:

tar -zcvf archive-name.tar.gz directory-name
  • c: create archive.
tar -xvzf example.tar.gz

To explain a little further, tar collected all the files into one package, example.tar. The gzip program applied compression, hence the gz extension. So the command does a couple things:

  • f: this must be the last flag of the command, and the tar file must be immediately after. It tells tar the name and path of the compressed file.
  • z: tells tar to decompress the archive using gzip
  • x: tar can collect files or extract them. x does the latter.
  • v: makes tar talk a lot. Verbose output shows you all the files being extracted.

Extracting bz2 files:

tar xvjf file.tar.bz2

Uncompressing tar file (.tar):

tar xvf file.tar

And to uncompress tar file (.tar) to another directory:

tar xvC /var/tmp -f file.tar

For zip and unzip:

Unzip file:

unzip xxx.zip ./

unzip xxx.zip ./

zip file:

zip xxx.zip zzz.xxx

zip a folder:

zip -r example.zip example/

19. Terminal New Tab

In terminal, press Control + Shift + T:

This operation will open a new terminal tab page in the same directory as the current one.

Press Control + Shift + W to close the current tab.

20. Terminate Ubuntu File Manager:

Sometimes, the Ubuntu file manager will get stuck, and we can’t open any folder or the trash can, we can terminate Nautilus by:

# If nautilus is in the middle of doing something you should use the first command as it allows nautilus to exit gracefully.data.
nautilus -q
# OR
killall nautilus

21. Convert audio from pcm to wav or from wav to pcm:

From wav to pcm:

ffmpeg -i file.wav -f s16le -acodec pcm_s16le file.pcm

From pcm to wav:

ffmpeg -f s16le -ar 44.1k -ac 2 -i file.pcm file.wav

where those parameters mean:

  • -f s16le … signed 16-bit little endian samples
  • -ar 44.1k … sample rate 44.1kHz
  • -ac 2 … 2 channels (stereo)
  • -i file.pcm … input file
  • file.wav … output file

22. Recursively delete all files with a given extension:

find . -name '*.o' -delete

23. Take screenshots:

PrtScSave a screenshot of the entire screen to the “Pictures” directory.
Shift + PrtScSave a screenshot of a specific region to Pictures.
Alt + PrtSc  – Save a screenshot of the current window to Pictures.
Ctrl + PrtScCopy the screenshot of the entire screen to the clipboard.
Shift + Ctrl + PrtScCopy the screenshot of a specific region to the clipboard.
Ctrl + Alt + PrtScCopy the screenshot of the current window to the clipboard.