man dhcpcd (Administration système) - a wrapper for the DHCP client daemon.
NAME
dhcpcd - a wrapper for the DHCP client daemon.
SYNOPSIS
dhcpcd <option> <interface>
DESCRIPTION
In Debian, the DHCP client daemon binary is called dhcpcd-bin and it is invoked via a wrapper called dhcpcd. Dhcpcd is normally invoked by ifup(8) but ifup only allows the setting of a limited number of dhcpcd command line flags. The dhcpcd wrapper reads extra flags from /etc/dhcpc/config and then invokes dhcpcd-bin(8) It also adds the hostname as an argument to the command line, unless it is already set by ifup or /etc/dhcpc/config or SET_HOSTNAME is configured. In that case there is no point in sending the old hostname with the DHCP request when it will be overridden by a new name supplied by the DHCP server.
Note that the interface argument must be supplied, there is no default to eth0 like the unadorned dhcpcd binary.
SEE ALSO
ifup(8) dhcpcd-bin(8)
AUTHORS
Simon Kelley <srk@thekelleys.org.uk>