Rob Norris
types, not as we know them
Michal writes about his continuing pain with the Amiga LONG
/ULONG
types on 64-bit AROS. Some guidelines for types:
- If you’re writing new code, just use the normal C types, and if you need types of a specific width, look to C99
uint32_t
, etc. On AROS,LONG
is always 32 bits, even on 64 bit systems. The C typelong
, however, can be 32 or 64 bits. Don’t assume they mean the same thing. - Don’t use
ULONG
,BYTE
,IPTR
, etc except when calling a system API that uses them, and then take care to make sure your type conversion is spot on. - The possible exception to this is
BOOL
, but only ever assignTRUE
orFALSE
to it, and never explicitly test its value; that is useif (flag)
, notif (flag == TRUE)
. - Don’t store pointers in non-pointer types. If you want a generic pointer, use
void *
. If you need to convert between an integral type and a pointer, useintptr_t
/uintptr_t
. - Don’t do clever bit things with bit fields, like Michal describes for
FHF_WRITE
. Just say what you mean.
This community service announcement brought to you by the variables i
, tmp
and foo
in the hopes that it helps the general health and wellbeing of people like Michal who have to decipher yours and my bad code by themselves years after it was written :)