Commands

curl cheat.sh/find | curl https://cheat.sh/find | bash alias: function ct { curl cheat.sh\/"$1"; } | on github | Cheat sheets: muo Vim | vim | tldr simpler man pages | find | awk | awk quickref | htg awk | sed | sed, htg | 13 CLI cmds | dig | netstat cmds | html | ls -Al | tr -s ' ' | cut -f9- -d' ' (list just file and folder names; -R for dir recursion) comm -12 <(sort file1.txt) <(sort file2.txt) find common lines in two files cat papers_to_read.htm | sort | cut -c 1-50 | uniq -d (find duplicate lines) gpg --output outfile.gpg --symmetric --cipher-algo AES256 file.ext | gpg -o original_file.txt -d file.txt.gpg | history -c chmod --reference=reference_file file | chown --reference=reference_file file | sudo systemctl -a | sudo systemctl --state active | sudo cp -p pedit.html blogview.html cp -rp doc | sudo chmod/chown --reference=f f1 [f2 f3] | grep -Eri '(Redirect|RewriteRule)' /etc/apache2/ host ipaddr|domain (Cloud Shell: get ip addr for domain or domain for ip addr, etc) find /tmp -type f -name ".htaccess" -exec grep -EHi '(Redirect|RewriteRule)' {} \; find . -maxdepth 1 -type f -name "*.md" -exec ls -al {} \; | whatis | free | find . -type f -perm 777 -exec chmod 644 {} \; | sudo apache2ctl -M (show all loaded modules) sudo apache2ctl -D DUMP_RUN_CFG | sudo apache2ctl -D DUMP_VHOSTS sudo apache2ctl -S (show parsed VHost settings) | sudo apachectl -t (apache config test) journalctl -u ssh.service | journalctl -u network.service | journalctl article | faillog netstat -tulpn | netstat -npl tar -cvzf archive-name.tar.gz directory-name | tar -C /diff-folder -xvf yourfile.tar to extract to a different directory | curl http://ipv4.icanhazip.com or curl http://icanhazip.com` or curl http://ip.fossdaily.xyz | curl --ssl | curl --insecure | curl -I http://domain.com (headers info) | wget --no-check-certificate zgrep -E "^(Remove:|Purge)" /var/log/apt/history.log* sudo iptables -L -nv --line-numbers | sudo iptables-restore < /etc/iptables/rules.v4 | lastlog | last install pkgs “kept back”: sudo apt-get dist-upgrade | sudo apt-get --with-new-pkgs upgrade | apt list --installed | grep " installed" /var/log/dpkg.log (also log.1) | apt show <pkg> | sudo -u www-data php occ app:list sudo systemctl list-unit-files | sudo systemctl list-unit-files | grep -i docker | sudo systemctl | grep running (list running services) sudo systemctl list-unit-files | grep enabled (list enabled services) apt-cache search php7.3 dpkg-query -L <package name> (list files in package) zip -d gallery.zip "picture_43_9.jpg" (delete file from zip, note zip goes first, followed by file)

netstat -plane | grep :80 | awk '{print $5}' | grep -Eo '([0-9]{1,3}\.){3}[0-9]{1,3}'| sort | uniq -c | sort -n conn port 80 perl -pi -e 's,RoseHosting,BestManagedVPS' file.php Replace all string instances w/o opening file w text editor find /home -type d -perm -o+w -exec ls -ld {} \; find world-writable directories in /home sed -e "s/\r//g" file > newfile remove newline chars from file
sed -i 's/search/repace/g' *.php replace string in all specified files
sudo sshd -T | sudo systemctl reload ssh.service | /etc/ssh/sshd_config | ssh security hardening | sudo lshw df -h | df -T systemctl list-unit-files --type=service systemctl list-dependencies graphical.target apt list --installed apt purge <unneeded package> sudo apt autoremove | sudo apt autoclean id <username> timedatectl | Bash date to/from unix epoch time: date +%s | date -d @<unix epoch time> | hostnamectl status lsb_release -a | cat /proc/version | gcloud info | gcloud version | Windows: netstat | findstr ESTABLISHED

Replace string recursively with find and sed Remove all dpkg rc residual packages

delete every line until PATTERN, that line included: cat index.html | sed '1,/body onload/d' print (p) from the first line matching PATTERN to the end ($): cat index.html | sed -n '/body onload/,$p'

Which Linux distro is running: cat /etc/*-release

text processing in the shell

dpkg queries:

-l, --list package-name-pattern...
    List packages matching given pattern.
-s, --status package-name...
    Report status of specified package.
-L, --listfiles package-name...
    List files installed to your system from package-name.
-S, --search filename-search-pattern...
    Search for a filename from installed packages.
-p, --print-avail package-name...
    On debian/ubuntu, use instead: apt-cache show package-name
    Display details about package-name, as found in /var/lib/dpkg/available.