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SubjectRe: [patch] s_maxbytes handling
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> > verification tests. So unless you can cite page and paragraph from SuS and
> > the LFS spec I think the 0 might in fact be correct..
>
> I don't know the standards Alan, but returning zero
> from write() when f_pos is at s_maxbytes will make
> a lot of apps hang up. dd, bash and zsh certainly do.

> Are they buggy? Should they be testing the return value
> of write() and assuming that zero is file-full?

0 is an EOF.

> The s_maxbytes logic is different from the
> MAX_NON_LFS logic:
>
> /*
> * LFS rule
> */
> if ( pos + count > MAX_NON_LFS && !(file->f_flags&O_LARGEFILE)) {
> if (pos >= MAX_NON_LFS) {
> send_sig(SIGXFSZ, current, 0);
> goto out;
> }
>
> This makes more sense. If the file is full, and
> you're trying to grow it, you fail.

The spec says of write

DESCRIPTION

For regular files, no data transfer will occur past the offset
maximum established in the open file description associated with
fildes.

[EFBIG]
The file is a regular file, nbyte is greater than 0 and the
starting position is greater than or equal to the offset
maximum established in the open file description associated
with fildes.

Which seems to say to me that if we write > 0 bytes and we start at or
on the boundary we should error - which would agree with your change.

Alan

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