Hi gurus,
Just learnt from my co-worker that it's safe to delete a null pointer. I
tried it on sun box
(and linux), nothing bad happens. So it seems to be true. But does it apply
to all platforms?
Also if I delete a pointer twice, and don't nullify the pointer after the
first delete, it's going
to trap. If I do the nullify, no trap. Does it just confirm that it's safe
to delete null pointer?
Btw I ran my test on SunOS 5.8 and Linux 2.4.18-3.
Thanks for your reply!
Songling
3  9589 
Songling wrote: Hi gurus,
Just learnt from my co-worker that it's safe to delete a null pointer. I
tried it on sun box
(and linux), nothing bad happens. So it seems to be true. But does it apply
to all platforms?
Also if I delete a pointer twice, and don't nullify the pointer after the
first delete, it's going
to trap. If I do the nullify, no trap. Does it just confirm that it's safe
to delete null pointer?
Btw I ran my test on SunOS 5.8 and Linux 2.4.18-3.
Thanks for your reply!
Songling
Calling delete on a null pointer is a no-op -- and, by the standard, no
problem. Of course, the fact that you're deleting a null pointer may
indicate the existence of a bug in your program -- but not necessarily.
HTH,
--ag
--
Artie Gold -- Austin, Texas http://it-matters.blogspot.com http://www.cafepress.com/goldsays
Songling wrote: Hi gurus,
Just learnt from my co-worker that it's safe to delete a null pointer. I
tried it on sun box
(and linux), nothing bad happens. So it seems to be true. But does it apply
to all platforms?
Also if I delete a pointer twice, and don't nullify the pointer after the
first delete, it's going
to trap. If I do the nullify, no trap. Does it just confirm that it's safe
to delete null pointer?
Deleting a null pointer is safe. 5.3.5/2 of the Standard:
"In either alternative, if the value of the operand of delete is the
null pointer the operation has no effect."
Regards,
Sumit.
--
Sumit Rajan <su*********@gmail.com>
"Songling" <ya******@nortelnetworks.com> wrote in message news:<co**********@zcars0v6.ca.nortel.com>... Hi gurus,
Just learnt from my co-worker that it's safe to delete a null pointer. I
tried it on sun box
(and linux), nothing bad happens. So it seems to be true. But does it apply
to all platforms?
Also if I delete a pointer twice, and don't nullify the pointer after the
first delete, it's going
to trap. If I do the nullify, no trap. Does it just confirm that it's safe
to delete null pointer?
Btw I ran my test on SunOS 5.8 and Linux 2.4.18-3.
Thanks for your reply!
Songling
Deleting a null poiner is fine. It will have no effect and will behave as expected This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
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