logger.1: Clarify -i flag

[fernape]

Summary

The PID of the logger process is always recorded along with the move from RFC
3164 to RFC 5424.

Indicate the -i flag is a no-op now in logger(1). We could probably remove the
-i flag since its presence does not seem to be enforced
but that might cause breakage in user scripts.

Related to a similary change in syslog.3.

Reported by: danfe@

Test Plan

logger "without pid?" && logger "with pid"

tail -f /var/log/messages
Mar 16 08:33:24 <<EDITED>> fernape[1858]: without pid?
Mar 16 08:33:24 <<EDITED>> fernape[1862]: with pid

• mandoc -T clean
• igor clean
• .Dd to be updated at commit time

[danfe]

The PID of the logger process is always recorded along with the move from RFC 3164 to RFC 5424.

Just to clarify: does the new RFC acutally require that PID is always recorded, or it's our local stupid enforcement?

[fernape]

In D34578#783358, @danfe wrote:

The PID of the logger process is always recorded along with the move from RFC 3164 to RFC 5424.

Just to clarify: does the new RFC acutally require that PID is always recorded, or it's our local stupid enforcement?

I don't think it is enforced by the RFC:
...The NILVALUE MAY be used when no value is provided...

[danfe]

@fernape wrote:

I don't think it is enforced by the RFC

I see. So it's another one of our many regressions in recent FreeBSD versions. :-(

[fernape]

Landed. Thanks!