ppp_register_compressor
int answer = ppp_register_compressor(&ppp_bsd_compress);
extern int ppp_register_compressor (struct compressor *cp);
extern int ppp_register_compressor (struct compressor *cp);
rc = ppp_register_compressor(&ppp_deflate);
rc = ppp_register_compressor(&ppp_deflate_draft);
EXPORT_SYMBOL(ppp_register_compressor);
answer = ppp_register_compressor(&ppp_mppe);
extern int ppp_register_compressor(struct compressor *);