What I mean is, compared to an interpreted programming language like Python. As far as I can tell, shell scripts are only really useful for administrative tasks, which could be done just as easily (?) in Python (or Perl, Ruby, etc.).

I want to eventually learn to program, and have my eyes on Python as a first language. Given that my interest is purely as a hobbyist, is it worth my time to learn shell scripting first?

Shell scripting is great for quick solutions.
Grep, sed, and awk are your friends.

I have performed so many things just by a simple shell script.

Shell scripting is easy to learn.

Also in conjunction with learning shell scripting you learn about Regular Expressions ... which is essential if you are dealing with other scripting such as Perl.

I have decided to learn shell scripting before I move on to Perl.

An interpreted language is generally kept on /usr, however your shells authorized for script execution are generally kept on /. This means that interpreted languages aren't always available during initial startup, so if you want something done at startup you should use a shell script.

Shell scripts are great for things that you would normally have to hand jam into a console each time you start your system. I use scripts to set up my system at startup, to include things like automatically detecting a USB drive so that it can mount encrypted file systems automatically, otherwise do "something else". I also use a script as a wireless LAN monitor so that if the link goes down then it will automatically reset it and bring it back up. All of these things I could do in an SU terminal, however it would be the same actions every time so I choose to make them scripts.

The bottom line is that if you know what you need to do in a terminal there is no sense trying to translate it into something besides what the terminal itself interprets.
ta0kira

Shell scripts support pipelines, the scripting-language analog of which (functional composition) is usually less-well supported (by the language). The flow of text as it is filtered and translated from one program to another is one thing that Unix shell scripting has always been very good at.

Shells are also much more lightweight than, say, a full-blown Perl interpreter.

Just a few reasons why shell scripting still matters. Not to say that I couldn't rewrite all my shell scripts in Perl or Python or Java or C, but I wouldn't want to. Neither would I want to rewrite my kernel in Ada, even though I could.

You also need to know how to shell script if you ever want to edit the startup scripts (rc.*) provided by your distro. Some people actually see that as strange, but on most systems it's required at some point. Better than having to come to LQ if you run into the smallest problems. That can take days, whereas knowing how a script works can ease the majority of your problems.
ta0kira

PS I think it's a fundamental *nix skill that should never be overlooked or dismissed!

The shell as a command line and the shell as a programming language is an artificial distinction. Knowing how to use the shell to launch programs, list files, pipe input from one program to input of another on the command line gives you all you need to write a simple shell script. This is a concept that most MS-DOS users can grasp when they write their first .bat file. However, MS-DOS has nothing to offer as a programming language, therefore this is a one way street.

The Unix shell, particularly Bourne Shell derivatives are different. Shell functions, for and while loops, if and case clauses and shell variables are all powerful tools at the command line.

I believe I'll go back to running DOS if I ever see that /bin/sh is a link to Python or Perl...
If Python was the main shell for Linux, it would take a *long* time to boot.

I think so, I get paid a nice living for it

Learn shell/Perl for simple administrative tasks and whose code doesn't go beyond what you can read and comprehend. Learn Python for doing more complex jobs, like text manipulations, formatting reports , socket programming, GUI programming and many more etc etc. Also, Python codes tend to be easy to read, understand and maintain.
Regular expressions are good, as some people said, but too much of it becomes unyieldy, hard to understand and difficult to troubleshoot for bugs, especially for a noob sysadmin. these are just my $0.02

if you are seriously going to do stuff on a linux/unix box
you cannot escape shell scripting.


it's all part of the tool box.

Hi, Canadakid.
Best wishes on embarking on a new adventure ... cheers, makyo

I'm a big fan of Python, but sometimes bash is just quicker and easier.

Yep. And everyone has already a shell installed on his/her system.

You might also ask, "Is Python really worth it, when I can re-write python programs in C?". The answer to both your question and this one is "yes". The reason is that some tasks are simply better suited to some languages.

Why write 20 lines of C when you can do a one-liner in perl or python? Maybe it's faster in C, but maybe the performance isn't worth the time spent in writing and debugging. Similarly, there will be tasks which are more easily accomplished using shell scripting.

There is no "one language to rule them all". Learn many languages, and choose the best suited to a given task. Be sensible of course - too much mixing can lead to a chaotic solution. The thing to do is learn about many, and then use your experience to judge what is a good solution to a problem.