Infrequently used usefull linux (debian) commands

linux-commnads.md

$ systemd-analyze # Analyze system boot-up performance

$ dmesg # display contents of kernel ring buffer

$ sudo dpkg -i /path/to/deb/file; sudo apt-get install -f
# install a .deb file with it's dependencies

$ dpkg -l | grep '^.i' # list installed packages

$ find . -type f -exec chmod -x {} \;
# remove execute permission from all files including
# files in sub directories

$ ifconfig # list available network interfaces

$ iwlist <wireless iterface> scan # list available wi-fi networks

$ cat .bash_history | sort | uniq
# list all history entries without duplicates

$ sudo apt-mark hold packages # prevent packages from being upgraded

$ dpkg --get-selections # shows packages with markers(install, etc..)

$ apt-get --reinstall install gdm3 gnome gnome-shell # reinstall Gnome

sources.list_for_debian_testing.md

# testing main
deb http://httpredir.debian.org/debian/ testing main contrib non-free

# testing-updates
deb http://httpredir.debian.org/debian/ testing-updates main contrib non-free

# testing security
deb http://security.debian.org/ testing/updates main contrib non-free