Re: Nulls get converted to 0 problem
От | kdebisschop@alert.infoplease.com |
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Тема | Re: Nulls get converted to 0 problem |
Дата | |
Msg-id | 1054918235.31564.1.camel@miles.debisschop.net обсуждение исходный текст |
Ответ на | Re: Nulls get converted to 0 problem (Samuel Tardieu <sam@rfc1149.net>) |
Список | pgsql-general |
On Fri, 2003-06-06 at 11:31, Samuel Tardieu wrote: > >>>>> "kdebisschop" == kdebisschop <kdebisschop@alert.infoplease.com> writes: > > kdebisschop> if (str == "") > kdebisschop> printf ("This comparison above can segfault on some > kdebisschop> systems\n"); > > No, it can't. You are comparing pointers (str and a pointer to a NULL > string). This is exactly the same as comparing integers. If any > compiler generates code which does a segmentation fault, it is far > from being (even remotely) a C compiler (and I'm not being pedantic > here). > > If you meant strcmp(str, "") that's a completely different story. I think you're right -- I was merely trying to illustrate that NULL and "" are not the same in C. My example should probably have been labelled as being more akin to psuedocode Thanks for the clarification. -- Karl DeBisschop <kdebisschop@alert.infoplease.com>
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