Messages in this thread | | | From | Michael Buesch <> | Subject | Re: [PATCH] Use NULL instead of integer 0 in security/selinux/ | Date | Thu, 8 Jul 2004 13:28:38 +0200 |
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Quoting "Richard B. Johnson" <root@chaos.analogic.com>: > Because NULL is a valid pointer value. 0 is not. If you were > to make 0 valid, you would use "(void *)0", which is what > NULL just happens to be in all known architectures so far, > although that could change in an alternate universe.
No, that is not true. In C/C++ this is true: NULL == 0
You can _always_ use 0 instead of NULL. The use of NULL is _only_ for readability reasons. When you assign 0 to a pointer, the compiler knows that you want to assign a NULL-pointer and not the value 0. Even on architectures where the NULL-pointer is not represented as 0 in memory (another bitmask), it's still valid to assign 0 to a pointer, because the compiler _knows_ that you are handling with a pointer and does The Right Thing (tm).
- -- Regards Michael Buesch [ http://www.tuxsoft.de.vu ]
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