In the pcap_list_datalinks() man page, refer to the
pcap_datalink_val_to_name() man page, as the routines described there
can be used to print out names and descriptive text for the values
returned by pcap_list_datalinks().
In the pcap_set_datalink() man page, refer to the
pcap_datalink_name_to_val() man page, as pcap_datalink_name_to_val() can
be used to convert a name for a link-layer header type into a value to
be handed to pcap_set_datalink().
Update the change date on some man pages while we're at it.
Have pcap_can_set_rfmon() return PCAP_ERROR_PERM_DENIED if you don't
have permission to check the device and PCAP_ERROR_NO_SUCH_DEVICE if
there's no such device, at least on Mac OS X. Other platforms need to
be fixed as well.
Update the documentatation to reflect that it can return
PCAP_ERROR_PERM_DENIED, fix a typo, and speak of capture sources rather
than devices.