Re: sizeof([ALLOCATED MEMORY])

Howard Hinnant wrote:
In article <eJ6dnTe9u7iOZMrZnZ2dnUVZ8sydnZ2d@xxxxxx>,
Richard Heathfield <invalid@xxxxxxxxxxxxxxx> wrote:

ballpointpenthief said:

If I have malloc()'ed a pointer and want to read from it as if it were
an array, I need to know that I won't be reading past the last index.
When you allocate the memory, you know precisely how much memory you are requesting.

Don't Forget (tm).

However when you allocate the memory, you don't know precisely how much you received. It could be more than you requested. And common applications exist which could make use of that extra memory if only they knew it existed (e.g. a dynamic array).
Why would they make use of more memory than they requested instead of
just requesting that much memory in the first place ?

Major OS's provide this functionality in a non-portable fashion. Imho C should provide a portable layer over this functionality.
No.
How horrible.
.

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