Useful Linux commands

Using bash

File compression

Extract from a tarball

tar -xf archive.tar -C /path/to/directory

where:

-x = extract
-f = file option input specifying location
-C = file option output specifying location

Grep

Using grep to search files and folders in a directory recursively:

grep -rni "string" *

where

r = recursive i.e, search subdirectories within the current directory
n = to print the line numbers to stdout
i = case insensitive search

See this post on StackOverflow.

Package management

Search for packages within APT

apt search package_name

File operations

Move files

mv is used to move and rename files/directories, usage:

mv [OPTIONS] SOURCE DESTINATION

Comparing the contents of two directories

diff -r <directory1> <directory2>

Finding all files containing specific string

grep -Rnw '/path/to/somewhere/' -e 'pattern'

Adding -l option provides file name containing result. See this StackOverflow post

Create a symbolic link

ln -s source symbolic_link

source can be a file or directory.

Hard disk

To display connected hard disks, mount points, etc

lsblk

Mounting a disk

Create a folder to mount:

sudo mkdir /media/disk

Then use mount:

sudo mount /dev/sda1 /media/disk

Repairing NTFS partition

Use ntfsfix, which is part of ntfs-3g.

Make sure disk is not mounted:

umount /dev/sda1

Then run nftsfix on disk:

sudo ntfsfix /dev/sda1

Be cautious, MS Windows utilities should be preferred.

Tasks / Processes

ps shows a list of running processes.

Article here details some of the switches, etc.

top provides a real-time list of running processes in order of CPU usage.

daniel-finnan/linux_commands.md