| Value | Meaning |
|---|---|
| None0 | |
| NI_NUMERICHOST1 << 0 | Don't try to look up hostname. |
| NI_NUMERICSERV1 << 1 | Don't convert port number to name. |
| NI_NOFQDN1 << 2 | Only return nodename portion. |
| NI_NAMEREQD1 << 3 | Don't return numeric addresses. |
| NI_DGRAM1 << 4 | Look up UDP service rather than TCP. |
| NI_IDN1 << 5 | Convert name from IDN format. |
| NI_IDN_ALLOW_UNASSIGNED1 << 6 | Don't reject unassigned Unicode code points. |
| NI_IDN_USE_STD3_ASCII_RULES1 << 7 | Validate strings according to STD3 rules. |
Flags supported by getnameinfo().