Contents of the QB4UN.DOC file
Undocumented command line options for BC.EXE (QuickBASIC 4.0)
/AM and /AL
I believe these, along with the documented /AH, set the amount of memory
allowed for arrays. /AL is the default setting. It's possible that the M,
L and H stand for MEDIUM, LARGE and HUGE.
BC internal representation - /AM = 0
/AL = 1
/AH = 2
Default value is 1.
Not known just what this one does yet. It DOES do something.
/FPA, /FPC, /FPC87, /FPI and /FPI87
/FPI is default. Changes the way floating-point routines are called within
your program. In my testing, /FPA, /FPC and /FPC87 all created an OBJ
module that needed an external library linked with it. The "C" appears to
stand for "CALL" while the "I" stands for "INTERRUPT". I haven't figured
out what the "A" stands for. By the way, BC does notice the difference
between /FPC and /FPC87 (likewise with /FPI and /FPI87). I haven't figured
out what the differences in output are yet. None of the machines I have
available for testing have the 80x87 and that may be important in this
BC internal representation - /FPA = 0
/FPC = 2
/FPC87 = 3
/FPI = 4
/FPI87 = 5
Default value is 4.
Noticeable differences between /FPC and /FPI
PRINT ATN(1) * 4 'calculated value for PI (3.14159)
int 35 ;FLD dword ptr 
int 3D ;FWAIT
int 34 ;FMUL dword ptr 
int 35 ;FSTP dword ptr [BX]
int 3D ;FWAIT
call __flds ;FLD dword ptr 
call __fmuls ;FMUL dword ptr 
call __fstsp ;FSTP dword ptr [BX]
Please send any comments to Michael Addy [74017,2437]. If it can be
determined exactly what these options do (instead of relying on my
guesswork), I will revise this file.