This function returns the start address of where the machine code routine for the given keyword is stored. If the keyword is unrecognised by the system, 0 will be returned. This command will work from MultiBASICs and Multiple SBASICs.
The file server functions of Toolkit II will only work if the code is in ROM, on an EPROM cartridge, under SMS or on a Trump Card for example.
Nevertheless, the FSERVE command is also found in the configurable software version. You can easily check what version of Toolkit II is present by looking at the base address of TK2_EXT and then adapt your program to take account of the system configuration.
100 TK2_location=KEY_ADD("TK2\_EXT") 105 FILE_SERVER=0 110 SELect ON TK2_location 120 = 48*1024 TO 64*1024: FILE_SERVER=1 130 = REMAINDER: IF VER$='HBA': FILE_SERVER=1 140 END SELect 150 : 160 IF FILE_SERVER THEN 170 FSERVE 180 ELSE PRINT "Sorry, no ROM based file server." 190 END IF
KEY_ADD does not produce an error (unlike ELIS) when a keyword is not found, and is therefore ideal to check if a certain Toolkit, command or function is present. This can be used within programs to adapt to available facilities.
In this example the internal date and time is saved as a hexadecimal number (this is more precise) if the necessary functions are present, otherwise it saves it as a floating point number.
The load routine then checks if the DATE was stored as a hexadecimal or decimal number, taking whatever action is necessary.
100 DateFile$="flp1_LastDATE_dat" 110 : 120 DEFine PROCedure WRITE\_DATE 130 IF KEY_ADD("OPEN_OVER") THEN 140 OPEN_OVER#3,DateFile$ 150 ELSE OPEN#3,DateFile$ 160 END IF 170 IF KEY_ADD("HEX$") AND KEY_ADD("HEX") THEN 180 PRINT#3,"$" & HEX$(DATE,32) 190 ELSE PRINT#3,DATE 200 END IF 210 CLOSE#3 220 END DEFine WRITE_DATE 230 : 240 DEFine PROCedure READ_DATE 250 LOCal d$ 260 OPEN_IN#3,DateFile$ 270 INPUT#4,d$: CLOSE#3 280 IF d$(1)="$" THEN 290 IF NOT KEY_ADD("HEX") THEN RETurn 300 d$=HEX(d$(2 TO)) 310 END IF 320 ADATE d$-DATE 330 END DEFine READ_DATE