When a call using XTF_NOSEL follows a click on the inactive tree, it returns the location of the click in the XTR.TARGETROW and XTR.TARGETCOL fields. This is useful in the following scenario:

Your program is waiting in some state other than XTREE (perhaps INFLD), but there is a visible (inactive) XTREE control on the screen. The user clicks on a cell in the XTREE. This returns the exitcode defined by XTR.KBDSTR to whatever routine is waiting on input. Your program sees that the exitcode is from clicking on the inactive XTREE, but you want to know what cell was clicked. So you call the XTREE, with opcode XTROP_RESELECT and with the XTF_NOSEL flag set (for an immediate exit). On exit, your program can get the location of the click from XTR.TARGETROW / XTR.TARGETCOL.

Note that this operation only makes sense in conjunction with XTF_MODELESS; also see xtrctl XTR.OPCODE.