You can download source code of "ash" and modify by yourself

You can download document from http://www.linuxfromscratch.org/lfs/download.html

and read about shell

Gedge your answer also sounds quite professional!! :)

em in the start of this profession and in second semmester of my degree!!

actually em not clear about chrooted environment!!! and i hav to do that program in windows not using terminal!!!

em confused abt the environment of the program,,, how would i store the data in a file!!1 i cant store it in a real file!!! so should i store it in arrays like things??? :(

I don't think chroot is the answer.

chroot stops those inside it from looking out (of the chroot'd tree), so any files/directories created in the chroot will be visible from outside the chroot (by the superuser, at least) - and I think the point is that the program is needed to see those files/dirs.

I suspect Aatif may want to create, say, a file which represents a virtual filesystem.

An example would be a 'dump' file - a file-based virtual filesystem that can be accessed using 'restore -i' (interactive, shell-like). Aatif probably has to design the format of the file and write the program to emulate an interactive 'restore' shell to access it.

Yes, that's right.

That's a great help !

Using this jail can I create a text file and folders etc and it won't be not accessible from outside ?

This might help. You could start by building the commands inside a chrooted environment.

A chroot just locks everything else out and you have to explicitly allow commands to be run (with your C program).

https://help.ubuntu.com/community/BasicChroot

http://www.kegel.com/cros ...