Using the ssgetfilter-list, you can select all entities containing extended data for a particular application. (See Extended Data - xdata.) To do this, use the -3 group code, as shown in the following example:
(ssget "X" '((0 . "CIRCLE") (-3 ("APPNAME"))))
This code will select all circles that include extended data for the "APPNAME" application. If more than one application name is included in the -3 group's list, an AND operation is implied and the entity must contain extended data for all of the specified applications. So, the following statement would select all circles with extended data for both the "APP1" and "APP2" applications:
(ssget "X" '((0 . "CIRCLE") (-3 ("APP1")("APP2"))))
Wild-card matching is permitted, so either of the following statements will select all circles with extended data for either or both of these applications.
(ssget "X" '((0 . "CIRCLE") (-3 ("APP[12]"))))
(ssget "X" '((0 . "CIRCLE") (-3 ("APP1,APP2"))))