From: Steffen Nurpmeso
> Sent: 01 March 2022 17:49
...
>
> David Laight wrote in
> <[email protected]>:
> |From: Denys Vlasenko
> |> Sent: 01 March 2022 16:40
> |> On Tue, Feb 15, 2022 at 12:31 PM Rob Landley <[email protected]> wrote:
> |>> On 2/14/22 10:09 AM, Roberto A. Foglietta wrote:
> ...
> |> My memory is hazy on this, but IIRC kernel also actually has some
> |> defensive code to not immediately reuse pids which just died.
> |
> |The Linux krnel only has protection for code inside the kernel.
> |Basically there is a ref-counted structure that you need to send the
> |signal - not the pid itself.
> |I can't quite remember whether the pid itself can be reused even before
> |that structure is freed.
> |
> |NetBSD does guarantee not to reuse a pid for a reasonable number
> |of forks after a process exits.
>
> ...which might be fruitless with 16-bit pids, define "reasonable".
Nothing stops pids going beyond 16 bits.
(Apart from some of the very old emulations.)
Much like nothing really requires the pid allocator to even start
allocating linearly (after giving init pid 1) - but that is
rather expected.
I can't remember at which point it went above 32767.
Was over 20 years ago when I wrote it :-)
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT,
UK
Registration No: 1397386 (Wales)
_______________________________________________
busybox mailing list
[email protected]
http://lists.busybox.net/mailman/listinfo/busybox
