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Jim Langston wrote: > ... > Do we know for a fact how a Null pointer is handled in RPG? Do we know, for >a fact, wither it is pointing to 0, or does it have a Null bit set? > ... There isn't any special RPG-ish way of dealing with pointers. On the as/400 (*), a pointer is a combination of 2 things: a 16 byte value with offsets etc, PLUS a bit somewhere in the system that says that particular 16 bytes really is a pointer. A pointer is null if that bit is not set. You set the bit on by doing a pointer operation on the 16 byte value (say assigning to the pointer). You set the bit off by explicitly assigning *NULL or by changing the 16 bytes in a non-pointer way (say you have the pointer in a data structure, and you assign to a character overlay of the pointer, although this may or may not invalidate the pointer if what you assign has a pointer in it). (*) This whole thing may not apply to teraspace pointers.
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