Re: 2.3 -> 2.4: long int too large to convert to int

Grant Edwards wrote:
> I give up, how do I make this not fail under 2.4?
>
> fcntl.ioctl(self.dev.fileno(),0xc0047a80,struct.pack("HBB",0x1c,0x00,0x00))
>
> I get an OverflowError: long int too large to convert to int
>
> ioctl() is expecting a 32-bit integer value, and 0xc0047a80 has
> the high-order bit set. I'm assuming Python thinks it's a
> signed value. How do I tell Python that 0xc0047a80 is an
> unsigned 32-bit value?
>
Everyone seems to be suggesting that the fix for the problem is to
somehow cobble together some way of forcing an unsigned integer into a
signed integer (what you would do with a cast in C). However, if I
understand the long<->int consolidation this is not consistent with that
effort.

As far as I can tell, the underlying problem is that the C routine
fcntl.ioctl is expecting a signed integer. These are the kinds of
problems that need to be fixed. The function should be asking for an
unsigned integer. This is possible with the C API at least since Python
2.3. Without these fixes, the long<->int consolidation is going to
continue to produce frustration. There are many functions in the
standard library that you would expect to take unsigned integers but
actually specify signed integers.
.

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