#ifdef HAVE_MINGW
extern const char *winerror(int);
#define strerror(x) ((x)>0?strerror(x):winerror(GetLastError()))
+#define sockerrno WSAGetLastError()
+#define sockstrerror(x) winerror(x)
+#define sockwouldblock(x) ((x) == WSAEWOULDBLOCK || (x) == WSAEINTR)
+#define sockmsgsize(x) ((x) == WSAEMSGSIZE)
+#define sockinprogress(x) ((x) == WSAEINPROGRESS || (x) == WSAEWOULDBLOCK)
+#else
+#define sockerrno errno
+#define sockstrerror(x) strerror(x)
+#define sockwouldblock(x) ((x) == EWOULDBLOCK || (x) == EINTR)
+#define sockmsgsize(x) ((x) == EMSGSIZE)
+#define sockinprogress(x) ((x) == EINPROGRESS)
#endif
extern unsigned int bitfield_to_int(void *bitfield, size_t size);