前缀在UNIX网络编程中是什么意思？

Question

When I was reading the book Unix Network Programming , there are many socket apis/types having prefixes like sin_addr with sin , inet_addr with inet , and in_addr_t with in . What do those prefiexes actually mean, that is, what are the full names?

Answer 1

I believe in the very early days structure members had to be unique. Using the same name for a member in two different structures failed. This is still (and always was) true for assembly macros that help use C structs and preprocessor macros.

The structures and constants from the old days therefor use a prefix that is usually derived from the structure name or context. Eg struct addressinfo uses a prefix of ai, struct sockaddr uses sa, struct sockaddr_in uses sin and so on.

Using unique names for each member allows using the same name for C and asm code, which made reading and writing code in both languages easier. No need to mentally switch tracks when switching language.