delphi - Why do I get an access violation when I call FillChar? -

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consider sample code:

var p512sector:pbyte; ..... getmem(p512sector, 262144); fillchar( p512sector,262144 ,0);

when run program, delphi gives me violation access error. why?

use fillchar(p512sector^, 262144, 0) (note dereferencing ^). otherwise overwriting pointer , stuff behind in memory, not allocated buffer.


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