Hi Brian, On Jan 7 15:39, Brian Inglis wrote: > getaddrinfo fails with err 7 EAI_NODATA for some valid hosts with A records. > Err 7 EAI_NODATA is mapped from WSANO_DATA err 11004 in Windows. > Can anyone reproduce failure with problem host name below? Yes, I can reproduce it, and it's a total surprise. In fact, this is *not* a Cygwin problem. I created an STC, a simple mingw application, very certainly not using Cygwin at all: $ cat gai.c #define _WIN32_WINNT 0x0a00 #include #include #include #ifndef AI_DISABLE_IDN_ENCODING #define AI_DISABLE_IDN_ENCODING 0x80000 #endif int main (int argc, char **argv) { WSADATA wsadata; struct addrinfo hint, *res; int ret; WSAStartup (MAKEWORD(2,2), &wsadata); memset (&hint, 0, sizeof hint); hint.ai_flags = 0;//AI_V4MAPPED | AI_ADDRCONFIG | AI_CANONNAME | AI_DISABLE_IDN_ENCODING; hint.ai_family = 0;//AF_INET; ret = getaddrinfo (argv[1], NULL, &hint, &res); printf ("ret = %d\n", ret); } $ x86_64-w64-mingw32-gcc -g -o gai gai.c -lws2_32 $ ./gai cygwin.org ret = 0 $ ./gai www.sun.de ret = 0 $ ./gai leapsecond.utcd.org ret = 11004 I have no idea why Windows' getaddrinfo chokes on leapsecond.utcd.org at all. Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Maintainer cygwin AT cygwin DOT com Red Hat