Re: pg_dump and large files - is this a problem?

Bruce Momjian wrote:
> > So I think we're wasting our time to debate whether we need to support
> > non-integral off_t ... let's just apply Bruce's version and wait to
> > see if anyone has a problem before doing more work.
>
> I am concerned about one more thing. On BSD/OS, we have off_t of quad
> (8 byte), but we don't have fseeko, so this call looks questionable:
>
> if (fseeko(AH->FH, tctx->dataPos, SEEK_SET) != 0)
>
> In this case, dataPos is off_t (8 bytes), while fseek only accepts long
> in that parameter (4 bytes). When this code is hit, a file > 4 gigs
> will seek to the wrong offset, I am afraid. Also, I don't understand
> why the compiler doesn't produce a warning.
>
> I wonder if I should add a conditional test so this code is hit only if
> HAVE_FSEEKO is defined. There is alternative code for all the non-zero
> fseeks.

Here is a patch that I think fixes the problem I outlined above. If
there is no fseeko(), it will not call fseek with a non-zero offset
unless sizeof(off_t) <= sizeof(long).

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