Curl to prompt a User Name and Password

I have a password protect web folder on my site, I am fetching that folder on another domain using Curl, what I want is: when I try to open the URL it should ask me the user name and password, instead of asking it display the "Authorization Required".

Example:

• http://www.example.com/admin (password protected using htpasswrd htaccess)
• http://www.2nddomain.com/admin

If I try to access the "a" url it ask me for the user name password. Fine. but it doesn't ask me for the user name and password on "b" (using curl here).

Any Idea?

In Short: I want to make Curl ask for the User/Password prompt.

Regards

I am not sure, if it is possible or not? but if it's possible so please let me know how, otherwise I will close this as "Invalid"