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Re: Off_t vs. off_t vs. int

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Nicholas Clark
November 12, 2003 14:51
Re: Off_t vs. off_t vs. int
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On Wed, Nov 05, 2003 at 05:57:38PM -0800, Stas Bekman wrote:
> Perl_pp_sysread uses int for its offset argument. PerlIO uses Off_t for 
> offsets. Should Perl_pp_sysread use Off_t as well? isn't int too small for 
> reading with large file supporting systems?

    int offset;

Mmm. yes, I suspect that it should based on a cursory glance.
Or at least the correct STRLEN type (as it's the offset into the scalar)

> Off_t is alised to off_t, but off_t is not in the typemap. should it be in 
> the typemap and be mapped to T_NV?
> Also the typemap defines:
> size_t                  T_UV
> ssize_t                 T_IV
> again aren't they too small for large filesystems?

Probably. Unless you compile perl with 64 bit ints.

>                                                    and should be T_NV?

Converting anything file size related from an integer to floating point
gives me the willies. Mainly because floating point will silently
lose precision once your files get larger than (say) 2**53
Seeking 1 byte wrong isn't that big a deal, is it?

I'm not sure that there is a good answer to any of this.

Nicholas Clark

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