Hi Luiz, Thanks for the quick reply! The platform i am using is rather unusual. Its a UNIX based proprietary RTOS with POSIX support. To add to complication i am compiling/linking in a cross-development environment running cygwin on WinXP. The gcc version i am using is 3.4.3 and linker version 2.15.94.0.1. Unfortunately, adding "-lsocket -lresolv -lrt" didnt help at all in my case Thanks again! -- View this message in context: http://lua.2524044.n2.nabble.com/symbol-not-found-h-errno-while-loading-LuaSockets-sockets-core-tp7647493p7647553.html Sent from the Lua-l mailing list archive at Nabble.com.