Co-ordinate Autolisp programming

[saifi2003]

How can i write a programme using offset command for selection.

[RobertB]

Your post was difficult to understand. Obviously you cannot use the offset command as as selection. So do you mean:
Indicate where you want a selection to occur, for instance, along a centerline; and have the selection be generated from an offset of the indication.
-or-
Selection some objects; and have them offset.