Linux Tricks Cheatsheet
Password Generators
$ brew install pwgen # MacOS
$ sudo dnf install pwgen # Fedora
$ pwgen 12
sei9AhPiokai jaezooThahn4 yahghooCh5ha uquiCh7soog0 Pahthe0fe5Ku owaht4xooPhu
eet2eijeeT6E Chie8oz1Enee Piemu7pi1uqu TheebohNg8se eil2AhNeiF2s WueGh8guoxie
$ sudo dnf install apg # Fedora
$ apg -n 3 -m 12 -M SNCL
|OgFeOcVask6
Aw*SwuKalap7
Nagnec8swif?
$ brew install gpg # MacOS
$ sudo dnf install gpg # Fedora
$ gpg --gen-random --armor 1 14
spdhuOS2il2JjhOq2ZU=
tree Directory Viewer
$ brew install tree # MacOS
$ sudo dnf install tree # Fedora
$ tree
$ tree /path/to/directory
$ tree [options]
$ tree [options] /path/to/directory
dnf Useful Commands
Fedora package installer DNF
$ sudo dnf install httpd # install httpd
$ sudo dnf install httpd-manual -y # assume yes
$ sudo dnf dnf check-update # check for available updates
$ sudo dnf update # updateb installed packages
$ sudo dnf install unbound-1.4.20-28.el7.x86_64.rpm # install local package
$ sudo dnf remove httpd # remove package
$ sudo dnf reinstall httpd -y # reinstall package
$ sudo dnf search php # search for a package
$ sudo dnf provides /etc/httpd/conf/httpd.conf # which package provides the file
$ sudo dnf info httpd #
$ sudo dnf repoquery --list httpd # list the files installed
$ sudo dnf history # installation history
$ sudo dnf history info 13 # what did install 13 do
$ sudo dnf history undo 13 -y # undo install 13
$ sudo dnf history redo 13 -y
$ sudo dnf list installed
$ sudo dnf grouplist # list which groups are available, installed, not-installed.
$ sudo dnf groupinfo "Web Server" # what is installed by this group
Terminal Pagers
Stolen from the Fedora Magazine: 5 cool terminal pages post.
$ more --help # trusty original with limited features
$ more <file> #
$ more <file1> <file2> <file3> # ':n' next file, ':p' previous file
$ less --help # many features
$ less <file> #
$ less <file1> <file2> <file3> # ':n' next file, ':p' previous file, ':e' new file
$ most --help # good for 'wide' files
$ most <file> # screens: 'ctl-x 2' split, 'ctl-x 1' close , 'ctl-x o' switch
$ most <file1> <file2> <file3> # split-screen and ':n' next file, ':p' previous file
$ pspg --help # table friendly pager
$ cat t.csv
a;b;c;d;e
1;2;3;4;5
$ cat t.csv | pspg --csv
mysql> pager pspg; # replace less or more as pager
$ export PAGER=pspg; mycli ... # MySQL CLI example
$ export PAGER=pspg; pgcli ... # PostygreSQL CLI example
Cat Tricks
$ cat -n <filename> # adds line number prefix
$ cat -e <filename> # shows crlf ending (Unix, DOS, MacOS)
$ cat -n <filename> | head -5 # (beginning) first 5 lines
$ cat -n <filename> | tail -5 # (ending) last 5 lines
$ cat -n <filename> | tail -10 | head -5 # (middle) first 5 of last 10 lines
Managing .rc files
By default, rcm uses ~/.dotfiles for storing all the dotfiles it manages.
A managed dotfile is actually stored inside ~/.dotfiles, and a symlinked.
For example, if ~/.bashrc is tracked by rcm, a long listing would look like this.
$ ls -l ~/.bashrc
lrwxrwxrwx. 1 link link 27 Dec 16 05:19 .bashrc -> /home/geoff/.dotfiles/bashrc
rcm consists of 4 commands:
mkrc– convert a file into a dotfile managed by rcmlsrc– list files managed by rcmrcup– synchronize dotfiles managed by rcmrcdn– remove all the symlinks managed by rcm
Brendan Gregg’s Homepage
G’Day. I use this site to share and bookmark various things, mostly my work with computers. While I currently work on large scale cloud computing performance at Intel (previously Netflix), this site reflects my own opinions and work from over the years. I have a personal blog, and I’m also on twitter.
This page lists everything: Documentation, Videos, Software, Misc. For a short selection of most popular content, see my Overview page.