SL> I used int 21h/48 to allocate some memory but failed. the file is .com
SL> Any ideas why it doesn't?                                              
Com files usually get ALL the memory when they are started, (not
just 64K), if you want to be allocated some memory there must be
some memory free! (you can either free some memory then allocate
what you need, or just check that you have enough.)
The word at (DS-1):3 will tell you how many paragraphs you have
available, but there's probably a interrupt service with the same
information.
Does anyone know if DOS will allocate UMBs if there's no free low
memory?
                        
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