Help commands.
Now what are the help commands that are used in a Linux environment that will give you some of the information
or some help about other commands?
There are three types of help command.
They are used in most of the Linux distributions.
The first one is what is.
So whenever you run a command, what is followed by the command that you want to inquire about?
You will run what is and space then command.
This will give you a quicker, a shorter version of the information about the command that you are looking
for.
The next one you have is the command, whichever command you want and lets the Ellis space and then
Dash Dash help.
This will give you a little a bigger, a longer version of the help of it.
More details about that.
The options about that command and the last one is man, which is stands for manual man space, followed
by the command, the command name itself.
When you run that, you will get a complete full listing of the command descriptions to help about it.
So now let's look at our Linux machine and we'll see how these commands work.
So we are here in our Linux machine, let's do the clear, and we will find out who we are again, who
am I?
We are ourself, you type clear.
The first command that we learned in Iran is what is it's all one word space, let's say else.
This will tell you the IS list, the directory contents.
The next one we will run is what a CD.
That's what tells you.
The bash built in command.
The CD is a bash built in command, meaning when you have your Linux system installed, it comes in
as pre-built command.
And what it does it change the working directory from one directory, of course, to another?
Well, let's try the same command to what is pWt tells you print name of current working directory return
working directory name.
So why do we have two different answers for one command is because we have two different sources or
two different dictionary already installed.
Or, you could say, two different mental pages installed on our on our Linux distribution.
There are there could be more that could be two, three, four or five, depending on what type of command
it is and what kind of description it has.
Let's look at the next command.
Let's say LS Dash Dash help.
See, there you go, it gives you a little longer description of your Ellis command.
And it tells you all the different options that are associated with a command.
So of course, right here, that's where it starts and it goes all the way down, tells you one option
minus a uppercase option and so on.
We could also run C-H Modi Dash Dash help.
I remember c h m Modica Dickerman is the change my command of a change the permission of a file.
So when we do help, we're going to see it tells you gives you a quick description starting from here.
It tells you that change the mod of each file to that are a file change to modify each file to mode
and a few different options.
Same thing.
You run this command with other different command space.
Does that help?
It will give you the information about a command.
Now, the last one we're going to look at is the MEN Command Man Central Mantle and then space.
Let's say Ellis and you run this command.
There you go.
I'll give you a very nice, descriptive way.
A nice formatted way of the user command.
Information tells you the name, the synopsis, the description.
At each option of that command, you could do space to go on each page.
Hit Space Bar Space Bar every time you want to quit out, just hit cue and you're going to be out of
it.
Same thing when you do a man command and then pwt, you do enter and you're going to see the exact same
thing pwt print name of the current working directory and what are the options it has?
My favorite command in all those help commands is this man command because it has exactly the information,
the detailed information of each command.