I try to build Stunnel 4.25 under VS2005 ,but failed cl -MD -W3 -Ox -O2 -Ob2 -Gs0 -GF -Gy -GL -nologo -I"..\..\ssl\inc32" -DUSE_WIN32 -D_CRT_SECURE_NO_DEPRECATE -D_CRT_NONSTDC_NO_DEPRECATE -DHAVE_GETADDRINFO -DHAVE_GETNAMEINFO -D_MBCS /c stunnel.c stunnel.c prototypes.h(428) : error C2081: 'socklen_t' : name in formal parameter list illegal stunnel.c(206) : error C2065: 'socklen_t' : undeclared identifier stunnel.c(206) : error C2146: syntax error : missing ';' before identifier 'addrlen' stunnel.c(206) : error C2065: 'addrlen' : undeclared identifier I use nmake -f vc.mak to do it Anyone has build it successfully ,pls help me ! Another way ,is there a stunnel solution or project file ? I also suggest build a windows client only version n It only can be running on windows n It only can act as a client n I think it can reduce the code size and runtime footprice smaller Thanks and best regards Eric dai