topic Re: learn scripting in Operating System - Linux

learn scripting

Shah Gaurang B. — Sat, 29 Jul 2006 08:02:37 GMT

Hi Friends,

I have to start scripting can you all experts guide me how to start and which books or documents will give me good guidance and help me to understand the concepts of scripting.

thanks to all in advance

Re: learn scripting

James R. Ferguson — Sat, 29 Jul 2006 08:20:49 GMT

Hi Shah:

There are many, many good books. However, a Google search for "shell scripting" will return a multitude of free tutorials.

A quick-read (free) book can be found here on HP's web:

http://www.docs.hp.com/en/B2355-90046/B2355-90046.pdf

This guide will give you a good, quick overview. Concentrate on the Posix/Korn shell since the Posix one is the standard HP shell. Too, out of this line (Posix/Korn) the 'bash' shell has evolved --- a standard in Linux.

An excellent site for scripts can be found here:

http://www.shelldorado.com/

This site has some good tutorials, guides to sound practices, and a fair number of scripts that allow you to see how someone else attacked a problem.

Regards!

...JRF...

Re: learn scripting

inventsekar_1 — Mon, 31 Jul 2006 09:36:42 GMT

Hi Shah,

In my view Better idea is to learn from others scripts.

find / -name *.sh

this will give you lot of scripts. view any thing u like. refer books or google after seeing the scripts.

All the best!!!
Keep learning!!!
Sekar

Re: learn scripting

James R. Ferguson — Mon, 31 Jul 2006 09:48:24 GMT

Hi (again):

There are two things wrong with:

# find / -name *.sh

The first is that should the directory contain more than one file ending in '.sh', then the 'find' command will *fail* with:

find: missing conjunction

To see why, do:

# echo *.sh

...and then consider that the entire evaluation is passed as an argument to 'find'.

The proper form would be:

find / -name "*.sh"

...which passes the argument intact to 'find' for its evaluation.

The second thing wrong with:

# find / -name *.sh

is the assumption that shell scripts must end with the '.sh' extension. They do not, and this is only a matter of choice. You will miss many, many good scripts making this assumption.

Regards!

...JRF...

Re: learn scripting

Marvin Strong — Mon, 31 Jul 2006 09:56:55 GMT

Another problem with reading someones script is unfortunatley not all admins comment their scripts well. So you learn some syntax or structure, but have no idea how or why it does what it does.

IMO reading others scripts is good, but first you have to understand what your reading thus have some basic shell scripting knowledge.

Tutorial sites, and books are great for getting this basic and even sometimes advanced knowledge.

Re: learn scripting

rmueller58 — Mon, 31 Jul 2006 10:03:06 GMT

There are two books I recommend as MUST have references..
Kochan and Wood - Shell Programming is a must

http://www.amazon.com/gp/product/0672324903/sr=8-2/qid=1154358108/ref=pd_bbs_2/104-8946161-4270352?ie=UTF8

Re: learn scripting

A. Clay Stephenson — Mon, 31 Jul 2006 10:06:59 GMT

I will also make the suggestion that you learn only a little shell scripting and instead concentrate on learning Perl. If you know Perl, you get all the power of the shell, awk, sed, and grep rolled into one tool. If I were starting over, that would be my approach.

Re: learn scripting

Jonathan Fife — Mon, 31 Jul 2006 10:09:39 GMT

If you have any sort of coding background, shell scripting will be cake. As for tools to get you started, it really depends on how you learn.

I'd suggest looking at online tutorials. They'll walk you through simple examples and get your feet wet. The ksh man page is also a very good reference, and being familiar with the different variables and builtins is helpful once you get going.

Once you're done with the basics, then I'd go hacking into scripts other admins have written. Documentation or no, if you have the fundamentals down (and google available), then you should be able to reverse-engineer pretty much any script out there.

If you feel the need for dead tree books:
Learning the Korn Shell
Classic Shell Scripting
both published by O'Reilly.

Re: learn scripting

Steven E. Protter — Mon, 31 Jul 2006 10:14:02 GMT

Shalom,

There are lots of good questions here on how to script this and that. Just spend 10 minutes a day reading the questions.

SEP

Re: learn scripting

inventsekar_1 — Mon, 31 Jul 2006 10:43:21 GMT

JRF,
thanks again for making me (and lot of others) clear...

/* is the assumption that shell scripts must end with the '.sh' extension. They do not, and this is only a matter of choice. You will miss many, many good scripts making this assumption. */

when he learn UNIX OS Structure well, they will come to know those scripts.
for the first time, they can try that one.. that is why i used that "find".

Re: learn scripting

Shah Gaurang B. — Mon, 31 Jul 2006 11:45:42 GMT

Thanks to all for the support.

Re: learn scripting

Shah Gaurang B. — Mon, 31 Jul 2006 11:47:55 GMT

thanks