How to define the root directory for any user, so that he cant go above his directory in Ftp Server.

I need help and suggestion about the wu-ftpd server .

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I need that when any user is connected to FTp server he can only view his home directory, means he can't able go go beyond his/her home directory or any other path which you have been set in password file as home directory. for example in case of anonymous access only the ftp
folder is the only root dirctory for anonymous users and can't able to view above then his ftp folder.
In linuc 6.2 path for ftp folder (/home/ftp).
In linux 7.x path for ftp folder (/var/ftp).
Directory view from the client side while connected from the anonymous users.
/
bin
lib
etc
pub

I have come to know that if you add /./ at the end of home directory path it is possible. To make it possible I have changed the home directory path adding /./ at the end for the root directory of asad user in the password file (etc/passwd) so that he can't able to go above his
home directory.

asad:x:500:100::/home/asad:/bin/bash (before changed )
asad:x:500:100::/home/asad/./:/bin/bash (after changed)

but nothing does effected at all .tell me if any other setting would be required in ftpaccess file for this solutions ?