Bash Scripting (CLI)...Please Help

[wyattwhiteeagle]

I didn't know which forum to post this in or how to make it "easy on the eyes"

The section below isn't exactly a "step by step" easy to follow guide.
It's a section at the Bash Scripting link in my signature.

I will be using this post as a guide for posting my questions.

Scripting

NOTE: The commands given in the scripting section are to be put into the text editor and not in the terminal unless instructed otherwise.
Bash is primarily a scripting language, so it would be a crime not to talk about scripting. Let's dive straight in with a bash script. More precisely the infamous "Hello World" script. You can create a bash script by opening your favorite text editor to edit your script and then saving it (typically the .sh file extension is used for your reference, but is not necessary. In our examples, we will be using the .sh extension).

#!/bin/bash

echo "Hello, World"The first line of the script just defines which interpreter to use. NOTE: There is no leading whitespace before #!/bin/bash. That's it, simple as that. To run a bash script you first have to have the correct file permissions. We do this with chmod command in terminal (change mode) as follows:
chmod a+x /where/i/saved/it/hello_world.sh #Gives everyone execute permissions
# OR
chmod 700 /where/i/saved/it/hello_world.sh #Gives read,write,execute permissions to the OwnerThis will give the file the appropriate permissions so that it can be executed. Now open a terminal and run the script like this:
/where/i/saved/it/hello_world.shHopefully you should have seen it print Hello, World onto your screen. If so well done! That is your first Bash script.

[wyattwhiteeagle]

The way I understood it, I open gedit, pasted the below making sure there was no "white space", clicked to save, named it "hello_world.sh" and saved it.
It saved to /home/wyatt.
When I ran /home/wyatt/hello_world.sh it said, "bash: /home/wyatt/hello_world.sh: Permission denied"

No where in the Guide does it say what to do if it doesn't "print on the screen"

The guide said that chmod will give permissions.

What did I do wrong?
How should it look?
How should I have ran it?

#!/bin/bash


echo "Hello, World"
chmod a+x /where/i/saved/it/hello_world.sh #Gives everyone execute permissions
# OR
chmod 700 /where/i/saved/it/hello_world.sh #Gives read,write,execute permissions to the Owner

wyatt@wyatt-Aspire-E1-532:~$ /home/wyatt/hello_world.sh
bash: /home/wyatt/hello_world.sh: Permission denied
wyatt@wyatt-Aspire-E1-532:~$

[deadflowr]

Those are two separate things.
The first is the script

#!/bin/bash

echo "Hello, World"

which you copy into a file and name that file something like hello-world.sh

The second is setting the required permissions for the file in order to run it.

chmod a+x /where/i/saved/it/hello_world.sh #Gives everyone execute permissions
# OR
chmod 700 /where/i/saved/it/hello_world.sh #Gives read,write,execute permissions to the Owner

The important part of this section are the parts before the # symbols as those parts are not read by the system.
They are typically used for comments about the commands like they do here.
So the actual commands would look this this

chmod a+x /where/i/saved/it/hello_world.sh

or

chmod 700 /where/i/saved/it/hello_world.sh

You only need to run one of those chmod commands.

[wyattwhiteeagle]

I changed it to...

#!/bin/bash         

echo "Hello, World"
chmod a+x /where/i/saved/it/hello_world.sh

Ran this in terminal

/home/wyatt/hello_world.sh

Terminal still says "Permission denied"

[deadflowr]

No.
The sections I posted are as they should be, don't combine things that aren't already combined.

The first part

#!/bin/bash

echo "Hello, World"

is to be saved as is to a file.
That's it.
That's the script.

The second part

chmod a+x /where/i/saved/it/hello_world.sh

is to be run inside a terminal.
This command is what sets to required settings in order to run the script.

Perhaps I should have clarified the point of running the chmod command in a terminal.
But I thought the wiki already explained that.

[wyattwhiteeagle]

Perhaps I should have clarified the point of running the chmod command in a terminal.
But I thought the wiki already explained that.

Thank you.
I will try that.

The Wiki says the below and so when I ran that, the terminal said "No such file or directory"

Now open a terminal and run the script like this:

/where/i/saved/it/hello_world.sh

Hopefully you should have seen it print Hello, World onto your screen. If so well done! That is your first Bash script.

[deadflowr]

The /where/i/saved/it/hello_world.sh is only an example name.
Unless you created it there is no such location as /where/i/saved/it.

What name did you save the file as?
And do you know where you saved the file?

[wyattwhiteeagle]

What name did you save the file as?
And do you know where you saved the file?

I must be either missing something or doing something wrong.

I named the file as hello_world.sh and saved it in /home/wyatt

I changed it to this...

#!/bin/bash


echo "Hello, World"

Changed to this and entered into the terminal...

chmod a+x /home/wyatt/hello_world.sh

And Terminal says...

wyatt@wyatt-Aspire-E1-532:~$ chmod a+x /home/wyatt/hello_world.sh
wyatt@wyatt-Aspire-E1-532:~$

That's all...terminal said nothing else and nothing else seems to have happened

Then I changed the a+x to 700...same thing...nothing from terminal and nothing happened

[The Cog]

This is all just basic stuff that a beginner has to get through. Don't worry, once you know what's going wrong it will all quickly make sense.
Two things I was told very early on when I started:
1- Linux generally says nothing if there's no problem. There's no "Yes I did that OK" message.
2 - Linux is case sensitive - this catches windows users out a lot. hello_world.sh and Hello_world.sh are different files, and both could exist next to each other.
So the face that this command didn't complain means it was successful, and execute permission has now been applied to that script file.

wyatt@wyatt-Aspire-E1-532:~$ chmod a+x /home/wyatt/hello_world.sh
wyatt@wyatt-Aspire-E1-532:~$

You should now be able to run the script with this command:

wyatt@wyatt-Aspire-E1-532:~$ /home/wyatt/hello_world.sh

[wyattwhiteeagle]

This is all just basic stuff that a beginner has to get through. Don't worry, once you know what's going wrong it will all quickly make sense.
Two things I was told very early on when I started:
1- Linux generally says nothing if there's no problem. There's no "Yes I did that OK" message.
2 - Linux is case sensitive - this catches windows users out a lot. hello_world.sh and Hello_world.sh are different files, and both could exist next to each other.
So the face that this command didn't complain means it was successful, and execute permission has now been applied to that script file.

wyatt@wyatt-Aspire-E1-532:~$ chmod a+x /home/wyatt/hello_world.sh
wyatt@wyatt-Aspire-E1-532:~$

You should now be able to run the script with this command:

wyatt@wyatt-Aspire-E1-532:~$ /home/wyatt/hello_world.sh

And we have success

Thank you so much for that info, it's enlightening


So...a recap...is this pretty much how it goes?

"Hello World" Basic Scripting

The Rules

In a text editor

1. #!/bin/bash must be the very first thing done in a text editor.
2. Must skip a line before typing a command
3. Command line must start with a command such as the word echo

In the terminal

1. chmod is a terminal command as though it's like someone's name inside the terminal
2. a+x is asking that person to do something specific
3. 700 (same as a+x and asks the same thing done)
4. a+x must be followed by the file location and filename ( /home/wyatt/file.sh )
5. The person, request, path, and filename must be on the same line

Instructions
The Script

In a prefered text editor. (Your choice. Doesn't matter which one...gedit; LibreOffice Writer)

1. Immediately type #!/bin/bash
2. Press enter twice
3. Type whatever command needed. (In this case, the command echo)
4. Hit the spacebar once
5. Type "Hello World" (be sure to include the quotation marks)
6. Click to save the file
7. Name the file including the extension as part of the filename, like this .sh (note the entire filename...in this case...file.sh)
8. Choose whare you want to save the file (note the location)
9. Save the file

Now in terminal
Activating The Script

1. type chmod a+x /home/wyatt/file.sh (where the file is saved and the entire filename)
2. Hit enter
3. Type /home/wyatt/file.sh (the path and filename)
4. Hit enter

The Terminal should say Hello World