I recently reinstalled my system with Slackware 12.2 (coming from 12.1), and during startup I see the following lines:

Polling for DHCP server on interface eth1:
/sbin/dhcpcd: invalid option – R
Polling for DHCP server on interface ath0:
/sbin/dhcpcd: invalid option – R
And I don’t get an IP address from dhcp due to this.

And in the message log I see the following for each reboot:
Messages log:
Jul 19 13:46:38 kayhermsen logger: /etc/rc.d/rc.inet1: /sbin/dhcpcd -d -t 30 -R eth1
Jul 19 13:46:42 kayhermsen logger: /etc/rc.d/rc.inet1: /sbin/dhcpcd -d -t 30 -R -R ath0

Looking into /etc/rc.d/rc.inet1 I see the line
[ "${DHCP_KEEPRESOLV[$i]}" = "yes" ] && DHCP_OPTIONS="$DHCP_OPTIONS -R"
And indeed I have DHCP_KEEPRESOLV[x]="yes" configured in /etc/rc.d/rc.inet1.conf for these two interfaces (for historical reasons).

Commenting out the DHCP_KEEPRESOLV[x]="yes" lines solves this issue, but I have to do that for all cards, see the double –R for ath0.
Commenting out the DHCP_KEEPRESOLV[x]="yes" line for only the ath0 which is at the end of the /etc/rc.d/rc.inet1.conf file still gives one –R option in the message file.

The man pages for dhcpcd doesn’t show this –R option.

Is this a known issue?
I looked into README.TXT and CHANGES_AND_HINTS.TXT

Not sure what version of dhcpcd you have - mines 2.0.8. This is from my copy of the man pages :

Thanks for letting me look to the version, I didn't notice (and didn't expect) that it is a DroplineGnome specific package.

cat /var/log/packages/dhcpcd-4.0.12-i686-1dl
PACKAGE NAME: dhcpcd-4.0.12-i686-1dl
COMPRESSED PACKAGE SIZE: 46 K
UNCOMPRESSED PACKAGE SIZE: 110 K
PACKAGE LOCATION: ./dhcpcd-4.0.12-i686-1dl.tgz
PACKAGE DESCRIPTION:
FILE LIST:

While on the disk 1 of the Slack 12.2 cd there is ./slackware/n/dhcpcd-2.0.8-i486-1.tgz

I probably have to address this to the DLG development team.