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interview Question - buffer overflow

 
Tiya Khambadkone
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given a buffer A (size unknown , length known) attach another buffer B to the end of buffer A such that A does not over-flow. both buffer's size is unknown and length is known.

How will you achieve this ?
 
Campbell Ritchie
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Is that actually a Java question? It sounds like the sort of thing which you do with malloc and clear, in C.
If it is an interview question, what did you say?
 
Winston Gutkowski
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Tiya Khambadkone wrote:given a buffer A (size unknown , length known) attach another buffer B to the end of buffer A such that A does not over-flow. both buffer's size is unknown and length is known.
How will you achieve this ?

Simple answer: Without
(a) some way of determining the "end" of a buffer.
AND
(b) some way of knowing the capacity of buffer A (note: NOT necessarily the same as its length).
you can't.

Winston
 
dennis deems
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Wouldn't this do the trick?

 
Henry Wong
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Dennis Deems wrote:Wouldn't this do the trick?




Sure, but it is also *not* needed. Remember that a string buffer will ensure its capacity automatically. You just append the other item, and it is done for you.


I am agreeing that this is likely a C question -- in that it is asking how to ensure capacity with a malloc'ed buffer.

Henry
 
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