BIO_C_GET_PROXY_PARAM
#define BIO_get_proxy_header(b,skp) BIO_ctrl(b,BIO_C_GET_PROXY_PARAM,0,(char *)skp)
#define BIO_get_proxies(b,pxy_p) BIO_ctrl(b,BIO_C_GET_PROXY_PARAM,1,(char *)(pxy_p))
#define BIO_get_url(b,url) BIO_ctrl(b,BIO_C_GET_PROXY_PARAM,2,(char *)(url))
#define BIO_get_no_connect_return(b) BIO_ctrl(b,BIO_C_GET_PROXY_PARAM,5,NULL)