If looking for environment variable MAIL env | grep MAIL # or find / -name 'mail' 2> /dev/null # / - is the location where it searches # -name 'mail' - is the query to search # 2> - error messages will redirected to nowhere

Server Message Block that Microsoft created for providing shared access to files and printers across nodes on a network. It also provides an authenticated inter-process communication (IPC) mechanism. SMB relies on the TCP and IP protocols for transport NetBIOS acronym for Network Basic Input/Output System provides services related to the session layer of the OSI model allowing applications on separate computers to communicate over a local area network Simply saying, it is a protocol that allows communication of files and printers through the Session Layer of the OSI Model in a LAN.[ ...

Unicode vs ASCII American Standard Code for Information Interchange (ASCII) launched in 1963 is used to translate human strings example ‘abcABC’ from their English characters to numbers that computers can read since computer can only read zeroes and ones (binary). The range is 0-127 so 128 English characters. Unicode - builds upon ASCII since 128 characters is limiting so Unicode includes other non English symbols such as ∆ + 💁 and Emoji + lets not forgot Chinese characters. There are more than 1.40.000 characters represented in Unicode. Unicode has various flavors such as UTF-8, UTF-16, UTF-32, etc. With UTF-8 used in over 90% of websites + most operating systems. The first 128 Unicode characters point to the ASCII characters to provide backward compatibility. ...

traditional style tar cfv etc.tar /etc # verbose output use the -v option tar -xvf archive.tar.bz2h v option requests the verbose operation c option requires creating the archive f option takes an argument that sets the name of the archive to operate upon.

wget -c ftp://ftp.vim.org/pub/vim/unix/vim-8.1.tar.bz2 -O - | sudo tar -xj Files that have a .tar.gz or a .tar.bz2 extension are compressed archive files. A file with just a .tar extension is uncompressed, but those will be very rare. The .gz or .bz2 extension suffix indicates that the archive has been compressed, using either the gzip or bzip2 compression algorithm. tar.bz2 file is a Tar archive compressed with Bzip2

search for a package Debian sudo apt-cache search <keyword>

grep -A # short for After -A num, –after-context=num Print num lines of trailing context after each match. See also the -B and -C options.

Configuring SSH for Remote Logins You can manually start the SSH service with systemctl start ssh or configure it to start at boot time with systemctl enable ssh. The SSH service has a relatively sane default configuration, but given its powerful capabilities and sensitive nature, it is good to know what you can do with its configuration file, /etc/ssh/sshd_config. All the options are documented in sshd_config(5) (see Manual Pages). The default configuration allows password-based logins. If this is not wanted, you can disable this by setting PasswordAuthentication to no. ...

Find Raspbery Pi Model commandline cat /proc/device-tree/model # Raspberry Pi 3 Model B Rev 1.2

List of all packages installed using Homebrew If you are not sure if you have installed a certain package such as gnu use the following brew list | grep gnu all including dependencies your installed Homebrew packages brew list items installed using Homebrew Cask. brew list --cask Shows you all top-level packages. That is packages that are not dependencies. This should be the most interesting if you are using the list to re-install packages. ...