ABAP : brows path file

PARAMETERS : p_path TYPE rlgrap-filename,
             p_file LIKE rlgrap-filename DEFAULT '/usr/sap/DEV/D00/data'.

at SELECTION-SCREEN on VALUE-REQUEST FOR p_file.

CALL FUNCTION '/SAPDMC/LSM_F4_SERVER_FILE'
 EXPORTING
   DIRECTORY              = p_file
   FILEMASK               = '*.*'
 IMPORTING
   SERVERFILE             = p_file
 EXCEPTIONS
   CANCELED_BY_USER       = 1
   OTHERS                 = 2
          .