Re: seekg calls in ls-mat5.cc

[David Bateman]

John W. Eaton wrote:

> There are a number of places in ls-mat5.cc where we have things like
>
>   is.seekg (tmp_pos + static_cast<std::streamoff> (PAD (len)));
>
> This seems risky to me because I don't think there is any guarantee
> that a cast from an integer type to a std::streamoff type is
> guaranteed to work (std::streamoff might not be implemented with a
> simple integer data type).
>
> Is it really necessary to save and restore the file position when
> reading MAT files or is there another way that we could implement
> these functions to avoid all the calls to seekg?
>
> jwe
>
>  
The seekg's in ls-mat5.cc are all to seek to a particular byte position 
in a file, to either take into account the padding, to skip an unknown 
length header, or an element that could not be read. The padding might 
easily be handled since we know the length we read and can just read a 
block that we don't use. However, the other two cases are harder to see 
what might be done, and in fact I have no solution..

You'll note I removed all of the seekp's recently..

Regards
David

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