Shell Scripting Tutorial for Beginners 4 - Pass Arguments to a Bash-Script

Passing arguments to a shell script

Any shell script you run has access to (inherits) the environment variables accessible to its parent shell. In addition, any arguments you type after the script name on the shell command line are passed to the script as a series of variables.

The following parameters are recognized:

$*
Returns a single string (``$1, $2 ... $n'') comprising all of the positional parameters separated by the internal field separator character (defined by the IFS environment variable).

$@
Returns a sequence of strings (``$1'', ``$2'', ... ``$n'') wherein each positional parameter remains separate from the others.

$1, $2 ... $n
Refers to a numbered argument to the script, where n is the position of the argument on the command line. In the Korn shell you can refer directly to arguments where n is greater than 9 using braces. For example, to refer to the 57th positional parameter, use the notation ${57}. In the other shells, to refer to parameters with numbers greater than 9, use the shift command; this shifts the parameter list to the left. $1 is lost, while $2 becomes $1, $3 becomes $2, and so on. The inaccessible tenth parameter becomes $9 and can then be referred to.

$0
Refers to the name of the script itself.

$#
Refers to the number of arguments specified on a command line.

★★★Top Online Courses From ProgrammingKnowledge ★★★

★★★ Online Courses to learn ★★★

★★★ Follow ★★★

DISCLAIMER: This video and description contains affiliate links, which means that if you click on one of the product links, I’ll receive a small commission. This help support the channel and allows us to continue to make videos like this. Thank you for the support!

[marklambert]

Good idea to show two screens, one with the editing and the other with output at the same time. Not many tutorials bother doing that.

[mamtachahal]

One of the best tutorials on Shell Scripting out there. Thanks a lot man, Appreciate your effort.

[charlesklein]

i have seen alot of videos and your are the most educational. you are the first person who video i saw after i went from w2k to Linux. you showed me how to load things. thank you!

[ShwetaSingh-ugtk]

best videos on shell scripting seen till date. Thanks a ton!!

[orestisiona]

This whole series is amazing. Thank you so much!. Viewing this in 2021!

[pmrm]

well, you have made shell scripting as easy as possible.

[fatehsinghsunny]

Hello
can you please explain in details why we need the Pass Arguments to a Bash-Script ?
please reply me as soon as possible.
And Thanks for wonderful tutorials for shell scripting language

[mamtachahal]

I know its very late, but one thing, at the end when the cards to some other videos and your channel's appear it blocks almost all the screen. 8:25

[surajkalyankar]

Hi sir, you expalained all videos nicely but have one doubt that all these videos are enough for 2+ exp or not?

[renishdevani]

Best explanation and it's helpful for the students like me whole series is outstanding thanks man ! and you also having nice voice .

[shwetasingh-xjlq]

it helped me in my script - array input as stdin. Thankyou for sharing this.

[Cerlienkus]

Hi
First of all good tutorial.
I've tried myself the examples in in this video but I've noticed a different behaviour.
When assigning to a variable the array of input parameters like you do with
args=("$@")
it seems to refer to all parameters except the script name
I've tried my script calling ./myscript.sh one two three
when it reached the statement
echo "Parameters from input: ${args[1]}, ${args[2]}"
I expected it to print "one, two". Instead it printed "two, three"
Modifing the statement like
echo "Parameters from input: ${args[0]}, ${args[1]}"
the result was what I expected
Also, statement
echo $@
seemed to print input parameters except script name.
How do you explain this?
Hallo and thanks from Italy

[tusharghude]

good tutorials
one request - please explain how array (or similar tool/program functionality) works in details before using them in examples

tip for beginners: if ur scratching ur head wondering why shell didnt print actual values but only variable names when he used
echo 'echo > $0 $1 $2 $3'
its because shell doesnt expand variables in single quotes (but it does in double quotes - see prev examples)

[ronaldmcsidy]

Need help from you man. It could save my job!! How do I create a shell script and run it in a remote system in-memory without actually creating the script file using ssh.

I cannot use scp

[venuvenu]

is " " really required in passing values/arguments/messages in the echo statement ?

[vaishnav]

Sir. ..one doubt..
cd command is not working when it is included in the bash script..
How to solve this problem 🤔🤔

[geniusworld]

sir can you please give us your source code it will more help us . to solving the problems

Make some apache videos later please too. Generically.

[dustybasement]

Dude im broke af but i would definitely contribute if you started a gofundme for these kind of videos

[shalvi]

Why did you put '> echo $1 $2 S3' ?
Even without that, it's displaying the result.