[fpc-pascal] Findfirst/findnext with a samba share

[Michael Van Canneyt]

On Fri, 1 Mar 2013, Ludo Brands wrote:

> On 03/01/2013 12:52 PM, Sven Barth wrote:
>
>> Currently FPC allocates only one pdirent in fpopendir
>> (rtl/linux/ossysc.inc). Maybe it should first stat the directory and
>> then decide based on st_blksize how much pdirent entries to allocate
>> (but it should also provide a sane default, as there is the possiblity
>> that st_blksize is 0 for a directory).
>>
>
> The dirent struct on linux contains a char d_name[256]; as the last
> element. The kernel returns only a null terminated string instead of the
> full 256 chars. Reason why you can get many files returned in one 280
> byte block. Allocating n pdirent entries for n files would be an overkill.
> The glibc getdents.c source uses some heuristics to determine how many
> entries will fit in a buffer. They use an average of 14 chars for the
> filename.
> The same source code also says in comments that the kernel limits the
> number of entries returned per call but doesn't say what the limit is.
> It probably depends on the underlying files system. This could explain
> why programs such as ls that use a 32k buffer never see the problem (at
> least I haven't found any reports).
> What about just using a 32k buffer?

No problem with that as far as I am concerned.

Since the code is shared between embedded and non-embedded targets, 
it might be better to have the option to specify the size of the 
buffer to use.

In recursive cases, it means that Depth*BufferSize buffers will be allocated.

Michael.