Bash Scripting 3 -- Variables and Quoting 

Bash Scripting 3 -- Variables and Quoting My Notes: What is this: $varname A variable - Why is it standard practice to put environment variables in all caps? They are outside the program (so you know not to mess with them) ie: $HOME (home directory) - What is this doing: myvar="This is so wonderful" Setting a variable (remember: no spaces) - What is this doing with the variable: echo "This is my ${some_number}th beer." Delimiting it (so that it can be inserted into a string - What is this doing with the information inside the ` ` characters: echo "there are `wc -l < /etc/group` lines in the /etc/shadow file" It is telling the shell that there is a command inside this string (and running it) - after, results are subbed in - Tell me if I missed anything. Be safe and have a great day.

hi , i would like to say "Thanks!" for your very nice and informative videos. I've learnt new stuffs by watching "The Linux Basics Course".

Just as I'd been wondering, after all these years, whether there is any bloody use to backquotes! Beautiful!

Loved this video and the bash scripting playlist in general. One thing I wanted to point out for anyone else interested is that there is a newer syntax for using the output of a command in variables or with the echo command like Dave did in the video here - using $(command) will do the same thing as `command`, but I personally prefer the $() syntax just because it’s easier for me to reach those keys and is a bit easier to see.

This was a succinct and informative video, thank you. Especially impressive since you were 9 beers deep.

Thanks younger pointing out the 'little things" like spaces, and their effect on the way the bash shell reads the program. I've read two books and watched 3 different series and that's the first time I have heard that tip.

Hi, thank you for your nice and educational videos. I'm glad that there are people like you who give linux some love and encourage people to try it out. I just wanted to note that there is another way of command substitution which I'm sure you know of, but should have mentioned it in this video: $(command) According to tldp this has superseded the quoting due to some advanced features like nesting. I haven't watched all of your videos, so if you already did mention this feel free to yell at me ;) If not, you may want to include this in one of your upcoming videos. Keep up the good work. Greetings BaBene

In addition, you forgot to change /etc/shadow to /etc/group in the message at around 8:30 . I commit these kind of gaffes more often than I like to admit as a teacher. Great series.

I was scratching my head earlier today when writing a bash oneliner to do a couple things. Of importance was being able to append the user defined input file. Didn't expect it to be as simple as >> ${varfile}_ Learn something new every day, thanks man!

Wow! I just wrote and program that deletes all screenshots in my desktop and tells me how many files I deleted. echo "`rm -v ~/Desktop/Screen\ Shot*.png | WC -l` files were deleted"

I didn't even know about the command substitution in the echo. Great video :-)

Your videos are the bomb man...

cant wait for the next one ! actually what i mean is that i AM WAITING for the next one..... you rock.

Thanks for leaving that cmatrix -abs on the screen, managed to find that screensaver.

Thanks, I learned this the hard way 😂 should have watched your videos 😂

Irrelevant to the point, but 69 lines in /etc/group not /etc/shadow.

Hello, thank you for videos! Why do you prefer 'wc -l < file' to just 'wc -l file'?

group 69 is a new concept to me))

Great explaining :)

Thanks for the all the tutorials! By the way, is that a shell screensaver??

Awesome..... Thanks.

Thank You Sir

how do you print out all the local variables you've created and how do you delete them?

Hello, first of all thank you so much for these videos, I am more addicted to them than to Silicon Valley (the show...). Anyway, I have a question. When we create those variables for the exercices, where do they go? Are they stored in some files and if so how can I delete them when I am done ? Thanks a lot Pascale

why does "sudo wc -l

isn't $(foo) a nicer way of `foo` ?

"A fortuitous number comes up"

Who are we? Programmers! What position do we like? 69!

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