CallWin32_Info
(SWI &C1000)

On entry:  -
On exit:
R0 =  Version of this module * 100
R1 =  Number of bytes in a parameter block
R2 =  Reserved
R3 =  Reserved
Interrupts: Interrupt status is unaltered
Fast interrupts are enabled
Processor Mode:  Processor is in SVC mode
Re-entrancy: SWI is reentrant
Use: This call returns information about the CallWin32 system. R1 is particularly of use as you need to pass workspace of at least that number of bytes to the CallWin32_Pars* SWIs (after initialising by CallWin32_ParsInit (SWI &C1002) of course).
Related SWIs: CallWin32_ParsInit (SWI &C1002)