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Date: Tue, 27 Apr 2021 12:06:51 -0400
From: Mike Frysinger <vapier@gentoo.org>
To: Peng Yu <pengyu.ut@gmail.com>
Cc: libc-help <libc-help@sourceware.org>
Subject: Re: Why is st_size defined as a signed int?
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On 27 Apr 2021 09:01, Peng Yu via Libc-help wrote:
> https://github.com/bminor/glibc/blob/master/bits/stat.h#L47
> 
> I see st_size is defined as __off_t, which should be a signed int. But
> can a file size be negative. If not, why not use an unsigned int to
> represent the file size? Thanks.

it's an offset, not a size.  lseek can legitimately be negative.

otherwise, at this point, the interfaces are ossified by POSIX, and glibc
simply has to match whatever it has.
-mike