摘要： 1.由名字查找某个熟知的端口struct servent{ char *s_name; /* official service name */ char **s_aliases; /* other aliases */ char s_port; /* prot ofr this service */ char *s_proto; /* protocol to use */};struct servent *sptr;sptr = getservbyname("smtp","tcp"));2.由名字查找协议struct pr... 阅读全文