shells and scripts


Trivia Category: Science: Computers
Difficulty: Medium
To bypass US Munitions Export Laws, the creator of the PGP published all the source code in book form.
True or False?

 
Thread Tools Search this Thread
# 1  
shells and scripts

So in UNIX, I understand that there are several different shells you can be in: C, Bourne, Bourne Again, Korn, etc. I also know that you can write scripts for the shells, by assigning it by #!/bin/csh, or sh, etc.

If I am working in the csh, do I have to write the script for the csh? Or can it be sh? If so, does the behavior vary if I am working in one shell, and write a script in another?

In my limited experience, I have to work in the csh, and I was writing a sh script, and things weren't working as expected. I changed the script to csh, and then the behavior was expected. Should this be expected?

Thanks in advance.
# 2  
csh is kind of an odd-man-out. It looks a little like other shell languages, but anything except trivial code turns out to be extremely different.

Most other shells are different varieties of Bourne shell. If you write a shell script using purely Bourne-shell features with no extensions, it ought to work in many or all of them. But if you use features specific to a certain shell, it may not play well with others. BASH and KSH both support arrays for instance, but do so in different ways...

You don't have to use the csh unless someone's forcing you to. It's a horrible language, and an optional thing you might find absent elsewhere -- unlike Bourne, which any UNIX system will have somewhere. Proficiency with Bourne isn't optional anyway, it's necessary for a variety of system things.

Last edited by Corona688; 02-14-2012 at 06:08 PM..
 

Previous Thread | Next Thread
Thread Tools Search this Thread
Search this Thread:
Advanced Search

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

Please what are shells?

I mean like this: http://shells.red-pill.eu/ Can anyone explain how this works? I hope my post is not spam. I think its related to linux. Thank you (1 Reply)
Discussion started by: postcd
1 Replies

2. UNIX for Dummies Questions & Answers

Shells

Lets say my default shell is bash and then i load up csh and then ksh. How would i exit csh without exiting ksh? so basically i gone from bash > csh > ksh and i wish to close csh (2 Replies)
Discussion started by: Bill Thompson
2 Replies

3. Shell Programming and Scripting

KSH - How to call different scripts from master scripts based on a column in an Oracle table

Dear Members, I have a table REQUESTS in Oracle which has an attribute REQUEST_ACTION. The entries in REQUEST_ACTION are like, ME, MD, ND, NE etc. I would like to create a script which will will call other scripts based on the request action. Can we directly read from the REQUEST_ACTION... (2 Replies)
Discussion started by: Yoodit
2 Replies

4. Shell Programming and Scripting

Changing the Bash Scripts to Bourne Scripts:URGENT

Hi, I have to write a program to compute the checksums of files ./script.sh I wrote the program using bash and it took me forever since I am a beginner but it works very well. I'm getting so close to the deadline and I realised today that actually I have to use normal Bourne shell... (3 Replies)
Discussion started by: pgarg1989
3 Replies

5. UNIX for Advanced & Expert Users

why we have different shells?

Can you pls. tell me, why we have different shells in UNIX OS ( Eg. SunOs) and also I would like to know what is the specific difference b/w SVR and BSD ? Thanks. (2 Replies)
Discussion started by: shahnazurs
2 Replies

6. Shell Programming and Scripting

control sub-shells

Hi all, New to shell scripting, I would like to know if it is possible to pass commands to a shell, which has been launched by a parent shell. Example: #!/bin/ksh # # Launch and command shells # . mySecondShell.ksh #this launches a sub-shell #now is something like this possible?... (7 Replies)
Discussion started by: MarkZWEERS
7 Replies

7. UNIX for Dummies Questions & Answers

How to open multiple shells while the scripts keeps running.

Hello, I've tried for a while now to run a bash script that continues to the end, while opening new shells as needed. I've tried xterm -e "somecommand"; & xterm -e " somecommand"; I've also tried screen -S "somecommand"; & screen -S "somecommand"; All without any luck, they... (5 Replies)
Discussion started by: Closed_Socket
5 Replies

8. Shell Programming and Scripting

Switching shells in UNIX Scripts

Solaris Newbie here to scripting in UNIX/SOLARIS. What I am looking to do is, once the script is executed, switch to /bin/bash shell and continue to execute the script. The problem I run into is once the script switches to the Bash shell, the script stops, and does not execute the... (2 Replies)
Discussion started by: Scoobiez
2 Replies

9. UNIX for Advanced & Expert Users

Shells

I have came across the definitions of these shells korn bourne c etc .. but honestly till now i din't get the exact difference between these threes , the advantages ..... can anyone pinpoint me where it actually lies ..... don;t include me answers like aliasing in c is posible and not in bourne ..... (3 Replies)
Discussion started by: dino_leix
3 Replies

10. Shell Programming and Scripting

%.*s function in shells

Can anyone tell me now to achieve the printf %.*s functionality in shell script, (sh/ksh). I want to append x number of (same)characters at the end of a file without using normal looping. Cheers. qanda (6 Replies)
Discussion started by: qanda
6 Replies

Featured Tech Videos