BPF packet filter and pcap_compile()

Short question: I am modifying some code that utilizes the BPF. The
filter is hard-coded in "packet filter assembler", but I would like to
use libpcap:s pcap_compile() function to create a filter from a command
string, e.g. "tcp and port 67 and ..." as in W.R. Stevens' UNP. Now my
question: The existing code does not use libpcap to open sniffing
devices etc, and I would like to keep it that way. However,
pcap_compile() needs a pcap_t device handle. Can I use libpcap
functions to open a sniffing device to create the pcap_t handle,
compile the filter with pcap_compile(), then use this filter with a the
/dev/bpf type device opened by the existing code? (the existing code
uses the same filter structs as libpcap)
(obviously, if the existing code opens a sniffing device that monitors
eth0, I would need to make the pcap_t handle also correspond to eth0)

Linux-specific solutions are OK at this point, but something portable
to Solaris or BSD is even better.

Best regards,

/Erik Alapää