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Re: Seek function

From: Georg Lippitsch <>
Date: Thu, 10 Jan 2008 10:40:08 +0100

Am Donnerstag, 10. Januar 2008 00:46 schrieb Daniel Stenberg:

> My main headache right now is to make the curl tool use it, and for that to
> work smoothly it can't use fseek() since that isn't doing 64bit seeks on
> Windows, so I need to switch to lseek() (and our lseek windows define
> trick) and for that to work I need to replace the existing fopen(), fread()
> calls and more... I think I'll save that work for a separate commit (and
> day) though.

You could define your own seek function that uses fseek multiple times like
this (not tested, but AFAIK should work with Windows):

#define MAX_SEEK_OFFSET 2147483647

void my_seek (FILE* hnd, curl_off_t offset, int origin)
    curl_off_t passed = 0;
    fseek(hnd, 0, SEEK_SET);
    do {
        long int new_offset =
            (offset > MAX_SEEK_OFFSET ? MAX_SEEK_OFFSET : offset);
        fseek(hnd, new_offset, SEEK_CUR);
        passed += new_offset;
    } while (passed != offset);
Received on 2008-01-10