Do it like this:
at selection-screen on value-request for p_tabname.
DATA: DNUM LIKE D020S-DNUM.
data: variant like rsvar-variant.
DNUM = SY-DYNNR.
CALL FUNCTION 'RS_HELP_HANDLING'
EXPORTING
DYNPFIELD = 'DATABROWSE-TABLENAME'
DYNPNAME = DNUM
OBJECT = 'TB '
PROGNAME = 'SAPLSETB'
SUPPRESS_SELECTION_SCREEN = 'X'
variant = variant.
regards,
Archer