NAME
    AvailMem -- memory available given certain requirements
SYNOPSIS
    size = AvailMem(attributes)
    D0              D1
    ULONG AvailMem(ULONG);
FUNCTION
    This function returns the amount of free memory given certain
    attributes.
    To find out what the largest block of a particular type is, add
    MEMF_LARGEST into the requirements argument.  Returning the largest
    block is a slow operation.
WARNING
    Due to the effect of multitasking, the value returned may not
    actually be the amount of free memory available at that instant.
INPUTS
    requirements - a requirements mask as specified in AllocMem.  Any
                   of the AllocMem bits are valid, as is MEMF_LARGEST
                   which returns the size of the largest block matching
                   the requirements.
RESULT
    size - total free space remaining (or the largest free block).
NOTE
    For V36 Exec, AvailMem(MEMF_LARGEST) does a consistency check on
    the memory list.  Alert AN_MemoryInsane will be pulled if any mismatch
    is noted.
EXAMPLE
    AvailMem(MEMF_CHIP|MEMF_LARGEST);
    /* return size of largest available chip memory chunk */
SEE ALSO
    exec/memory.h