Visit Our UNIX and Linux User Community


Creating new shell in C


 
Thread Tools Search this Thread
Top Forums Programming Creating new shell in C
# 1  
Old 06-05-2001
Creating new shell in C

Hi,
I am a student and I want to create a shell in C language.
The shell must be able to take commands(with arguments) from the user and execute them and show the results. Any help or ideas or any suggestions would be greatly appreciated.
Thanks
# 2  
Old 06-05-2001
Here's what I expect a shell to do:

Display a prompt
Accept input
Parse input (wild-card/alias expansion, etc)
Pass input to "exec"
Repeat


HTH
# 3  
Old 06-05-2001
Hi,
I know what the shell must do butI want to know how to do it?
Thanks
# 4  
Old 06-06-2001
Nobody is going to write an entire shell for you here in the forums. If you want to see examples of how a shell works, download the source code to one of the many free versions, such as <A HREF="http://www.kornshell.com">ksh93</A>, tcsh, etc.

Last edited by PxT; 06-06-2001 at 02:53 PM..
# 5  
Old 06-06-2001
I thought PxT gave a very good reply on the high level requirements for a shell. Combined with a followup suggestion to review existing source code for shells is an excellent reply.

If anyone wants to followup with high-level requirements for a shell, or perhaps what a shell should do that current shells do not (based on network-centric models, perhaps?) that would be great!

Previous Thread | Next Thread
Test Your Knowledge in Computers #934
Difficulty: Medium
The C standard library does not specify any specific resolution, epoch, range, or datatype for system time values.
True or False?

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Need help in creating arrays using shell

Hi, I need help in creating a array in shell scirpt. I have a file which has following details. hostname devices device1 device 2 de abcdmhs10 1234 2343 2353 3343 3435 2343 bcdfmhs11 2343 2443 3434 8874 0343 3434 (5 Replies)
Discussion started by: jpkumar10
5 Replies

2. Shell Programming and Scripting

Help with shell script - creating users

echo -e "Enter in a username : \c" read username grep "^$username:" /etc/passwdWhat I'm trying to do is take in a username from my script and I need to be able to check if that username already exists. If it does the script should display a message saying that the user already exists and exit. ... (2 Replies)
Discussion started by: shadowcat
2 Replies

3. Shell Programming and Scripting

Creating background process for my shell

I actually posted this problem on a different forum, but figured this would be a more appropriate place to post it. OK so I've created my own shell, but I can't get the background process function to run properly! What I want to do is to run a process in the background, and also print when the... (2 Replies)
Discussion started by: hansel13
2 Replies

4. Shell Programming and Scripting

Creating a command on a BASH shell

Hi all. Suppose I have the following function in an executable file named "HOLA": ------------------------ function hola { echo "Hola ${@}."; } ------------------------ In addition, suppose that I want to execute the file so I can input my name next to ./HOLA. I mean,... (4 Replies)
Discussion started by: hresquivelo
4 Replies

5. Shell Programming and Scripting

need help creating a shell that generates another shell

hi all, i'm trying to create a shell script that browse files in a directory and generates another shell script based on these files. for ex: /tmp/files/ is the directory i want to browse and it has 2 files file1.sh and file2.sh. now my shell script should browse /tmp/files/ and... (6 Replies)
Discussion started by: adshocker
6 Replies

6. UNIX for Dummies Questions & Answers

Java or C for creating a unix shell?

Hi, Great to find this forum! I'm a complete newbie to unix, and am having a hard time finding my way around. Firstly, I've been reading something about c shell programming being one tenth the size of c programming done on unix.....I couldn't figure what that meant, but there were two... (7 Replies)
Discussion started by: sdsd
7 Replies

7. Shell Programming and Scripting

Shell script creating too many processes.

I have a shell script that I am running every 60 seconds, but it is creating this process to the point that it is causing the server to perfrom poorly. Below is my script, what can I change to prevent this? while true do java -classpath .....( all my classes here) >/dev/null 2>&1 ... (3 Replies)
Discussion started by: Miller_K
3 Replies

8. UNIX for Advanced & Expert Users

Creating database in shell, how?!

Hi, i'm newbie in Unix. How can i create my own database in unix shell? Not to create a database through shell to MySql, oracle etc, but to create a completely mine database system through shell. Please help me, give me directions, i'm desperate :( (1 Reply)
Discussion started by: vants
1 Replies

9. Shell Programming and Scripting

Creating my first Shell Script

I have an assignment in my programming class to write a shell script that will use command line parameters, display the # of parameters, display all parameters on the command line and display the parameters $0-$9. I understand some of the code (I will be using 'n' to represent the count through... (1 Reply)
Discussion started by: plmahan
1 Replies

10. Shell Programming and Scripting

help on creating shell script

Can some one smart here help I need to create a shell script that does this below using vi editor. decrypts a file (specified as an argument to the script) containing text which was encrypted using the ROT-13 algorithm. The decrypted text should be written to a new file leaving the input file... (1 Reply)
Discussion started by: master_6ez
1 Replies

Featured Tech Videos