We already have discussed about a few good alternatives to Man pages. Those alternatives are mainly used for learning concise Linux command examples without having to go through the comprehensive man pages. If you're looking for a way to easily and quickly learn a Linux command, those alternatives are worth trying. Now, you might be thinking - how can I create my own man-like help pages for a Linux command? This is where "Um" comes in handy. Um is a command line utility, used to easily create and maintain your own Man pages that contains only what you've learned about a command so far.
By creating your own alternative to man pages, you can avoid lots of unnecessary, comprehensive details in a man page and include only what is necessary to keep in mind. If you ever wanted to created your own set of man-like pages, Um will definitely help. In this brief tutorial, we will see how to install "Um" command line utility and how to create our own man pages.
Um is available for Linux and Mac OS. At present, it can only be installed using Linuxbrew package manager in Linux systems. Refer the following link if you haven't installed Linuxbrew yet.
Once Linuxbrew installed, run the following command to install Um utility.
$ brew install sinclairtarget/wst/um
If you will see an output something like below, congratulations! Um has been installed and ready to use.
[...] ==> Installing sinclairtarget/wst/um ==> Downloading https://github.com/sinclairtarget/um/archive/4.0.0.tar.gz ==> Downloading from https://codeload.github.com/sinclairtarget/um/tar.gz/4.0.0 -=#=# # # ==> Downloading https://rubygems.org/gems/kramdown-1.17.0.gem ######################################################################## 100.0% ==> gem install /home/sk/.cache/Homebrew/downloads/d0a5d978120a791d9c5965fc103866815189a4e3939 ==> Caveats Bash completion has been installed to: /home/linuxbrew/.linuxbrew/etc/bash_completion.d ==> Summary ? /home/linuxbrew/.linuxbrew/Cellar/um/4.0.0: 714 files, 1.3MB, built in 35 seconds ==> Caveats ==> openssl A CA file has been bootstrapped using certificates from the SystemRoots keychain. To add additional certificates (e.g. the certificates added in the System keychain), place .pem files in /home/linuxbrew/.linuxbrew/etc/openssl/certs and run /home/linuxbrew/.linuxbrew/opt/openssl/bin/c_rehash ==> ruby Emacs Lisp files have been installed to: /home/linuxbrew/.linuxbrew/share/emacs/site-lisp/ruby ==> um Bash completion has been installed to: /home/linuxbrew/.linuxbrew/etc/bash_completion.d
Before going to use to make your man pages, you need to enable bash completion for Um.
To do so, open your ~/.bash_profile file:
$ nano ~/.bash_profile
And, add the following lines in it:
if [ -f $(brew --prefix)/etc/bash_completion.d/um-completion.sh ]; then . $(brew --prefix)/etc/bash_completion.d/um-completion.sh fi
Save and close the file. Run the following commands to update the changes.
$ source ~/.bash_profile
All done. let us go ahead and create our first man page.
Create And Maintain Your Own Man Pages
Let us say, you want to create your own man page for "dpkg" command. To do so, run:
$ um edit dpkg
The above command will open a markdown template in your default editor:
My default editor is Vi, so the above command open it in the Vi editor. Now, start adding everything you want to remember about "dpkg" command in this template.
Here is a sample:
As you see in the above output, I have added Synopsis, description and two options for dpkg command. You can add as many as sections you want in the man pages. Make sure you have given proper and easily-understandable titles for each section. Once done, save and quit the file (If you use Vi editor, Press ESC key and type :wq).
Finally, view your newly created man page using command:
$ um dpkg
As you can see, the the dpkg man page looks exactly like the official man pages. If you want to edit and/or add more details in a man page, again run the same command and add the details.
$ um edit dpkg
To view the list of newly created man pages using Um, run:
$ um list
All man pages will be saved under a directory named
.umin your home directory
If you don't want a particular man page, simply delete it as shown below.
$ um rm dpkg
To view the help section and all available general options, run:
$ um --help usage: um <page name> um <sub-command> [ARGS...] The first form is equivalent to `um read <page name>`. Subcommands: um (l)ist List the available pages for the current topic. um (r)ead <page name> Read the given page under the current topic. um (e)dit <page name> Create or edit the given page under the current topic. um rm <page name> Remove the given page. um (t)opic [topic] Get or set the current topic. um topics List all topics. um (c)onfig [config key] Display configuration environment. um (h)elp [sub-command] Display this help message, or the help message for a sub-command.
To view the current configuration, run:
$ um config Options prefixed by '*' are set in /home/sk/.um/umconfig. editor = vi pager = less pages_directory = /home/sk/.um/pages default_topic = shell pages_ext = .md
In this file, you can edit and change the values for pager, editor, default_topic, pages_directory, and pages_ext options as you wish. Say for example, if you want to save the newly created Um pages in your Dropbox folder, simply change the value of pages_directory directive and point it to the Dropbox folder in ~/.um/umconfig file.
pages_directory = /Users/myusername/Dropbox/um
Hope this helps.