| Value | Meaning | 
|---|---|
| None0 | |
| AI_PASSIVE1 << 0 | Socket address is intended for bind.  | 
| AI_CANONNAME1 << 1 | Request for canonical name.  | 
| AI_NUMERICHOST1 << 2 | Don't use name resolution.  | 
| AI_V4MAPPED1 << 3 | IPv4 mapped addresses are acceptable.  | 
| AI_ALL1 << 4 | Return IPv4 mapped and IPv6 addresses.  | 
| AI_ADDRCONFIG1 << 5 | Use configuration of this host to choose returned address type.  | 
| AI_IDN1 << 6 | IDN encode input (assuming it is encoded in the current locale's character set) before looking it up.  | 
| AI_CANONIDN1 << 7 | Translate canonical name from IDN format.  | 
| AI_IDN_ALLOW_UNASSIGNED1 << 8 | Don't reject unassigned Unicode code points.  | 
| AI_IDN_USE_STD3_ASCII_RULES1 << 9 | Validate strings according to STD3 rules.  | 
getaddrinfo() flags.