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just a theoretical question this time. Lets suppose i have an array with n elements . Obviously the elements can be indexed by 0 to n - 1. However the question is does pointing the index at element n cause a seg fault or trying to access the data stored there cause the seg fault.
You can point at the Nth element just fine.
So this is legal.
for ( p = array ; p < &array[N] ; p++ )
Dereferencing such a pointer however is always a bad idea.
Whether you get a segfault because of it depends on your luck.
I.e., if you're lucky you WILL get a seggy. :)Quote:
Whether you get a segfault because of it depends on your luck.
Seg faults sre usually generated by the OS.Quote:
Originally Posted by cooper1200
On most hardware the segfault occurs when you try to access a virtual memory address where the OS doesn't know how to map it to a physical address.
Most common is for addresses around 0 when a NULL pointer is deferenced, but you also do so by accessing a virtual memory address outside of those assigned to the stack, the heap or the program's code area (and many others type of memory that a process might allocate).
Virtual memory is given to your process in pages (maybe with a size of 4KB), so if you access outside an array by a little bit you wont usually cause a seg fault. Examples of this could be accessing an array with an index of -1 or that of the number of elements in the array - usually these result in unexpected memory corruption, not a segfault.