Re: [PATCH] printk: Let %pR handle NULL pointers

On Sat, 03 Jan 2009 21:02:15 PST, Trent Piepho said:

resource pointer.  Maybe "[]" or "[-]" would be better?  A null MAC address
could be ":::::" or "x:x:x:x:x:x".  "N.U.L.L" or "x.x.x.x" for a null IP4
address.  And so on.  So the printout looks nicer when a NULL pointer isn't
a bug.

Have to be careful for IPv6 addresses - '::' is a legal representation of
an all-zeros address.  Also, N.U.L.L. may give indigestion to logfile parsers
that are expecting a numeric value in the IP address.  It's however unclear
whether we should pick something that doesn't have 3 periods in it, so it
can't match, or whether *that* will give regexp-based logfile readers
indigestion when they don't pick up an IP address where they expected...

Do we want the %pI6 format to do the multiple-zeros -> :: compression?

(Adding netdev to cc: list)