[ntp:questions] new driver development

Martin Burnicki martin.burnicki at meinberg.de
Wed Mar 30 09:38:01 UTC 2011


David L. Mills wrote:
> Martin,
> This is the same issue with OpenSSL. If you have it, use it; otherwise,
> use whatever else is available. The application programs that might use
> the driver have the same issues. You could do it also with mode codes,
> but that is counterproductive in view of the shrill rhetoric to use
> POSIX if available.

In my opinion there's a difference between using OpenSSL and supportin Posix

If OpenSSL is available then ntpd can use it, otherwise it can not.

With the example you have provided:

>>>#ifdef POSIX

then, if Posix is supported, the legacy SHM interface is not supported.

This means if a new version of ntpd became available which supported Posix
SHM it would not support legacy SHM anymore, and e.g. an existing gpsd
could not be used anymore until it had also been upgraded to support Posix
SHM. If there are other programs beside gpsd which can feed the legacy SHM
then the same problems would arise for those programs.

If ntpd continues to support legacy SHM support, and Posix SHM in addition,
if available, then existing versions of gpsd could feed the legacy SHM, or
new versions of gpsd could feed the Posix SHM.

If I've understood correctly then this is also what Dave Hart suggests.

Martin Burnicki

Meinberg Funkuhren
Bad Pyrmont

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