Roadshow cleanups, Wait Writing return code fixes

API.md

@@ -123,9 +123,11 @@ a remote socket to send you data.
 
 ##### Returns
 
-* 0 on timeout
-* -1,-2 on error
-* 1 on success
+* 0 on timeout.
+* -1 on error. Use `Socket Errno` for more detail.
+* -3 on the socket being sorta-ready. This isn't a connection timeout,
+  so check again.
+* 1 on success.
 
 #### RESULT=Socket Async Wait Writing(Socket, Wait_ms)
 
@@ -135,9 +137,11 @@ has been completed.
 
 ##### Returns
 
-* 0 on timeout
-* -1,-2 on error
-* 1 on success
+* 0 on timeout.
+* -1 on error. Use `Socket Errno` for more detail.
+* -3 on the socket being sorta-ready. This isn't a connection timeout,
+  so check again.
+* 1 on success.
 
 #### RESULT=Socket Set Timeout(Socket, Wait_ms)
 

README.md

@@ -139,6 +139,11 @@ Doing something cool with the extension?
     most system-friendly way of doing this.
 * MiamiDX can be fiddly, at least it is on my MiSTer set up.
   If Internet connectivity is not working, try re-connecting to the network.
+* If using Roadshow, `bsdsocket.library` will always be available, so
+  you can't use its presence or lack thereof to test if Internet is available.
+  You'll have to use a combination of DNS lookups and/or connection
+  timeouts using `Socket Async Wait Writing` to determine if the Internet
+  is available.
 
 ## Versioning
 

src/BSDSocket.s

@@ -1576,6 +1576,7 @@ _DoSocketLibraryClose_Skip:
 ;
 ;   @return
 ;     1 on success
+;     -1 on error, check Socket Errno
 ;     -2 on library not open
 ;     -3 on not interesting yet
 ;     0 on timeout
@@ -1627,8 +1628,13 @@ _SocketWaitAsyncWriting_LibraryOpen:
         MOVE.L BSDSocketBase-MB(A4),A6
         CALLLIB WaitSelect
 
-        TST.L D0 ; timeout, pass through
-        BPL _SocketWaitAsyncWriting_Done
+        ; returns:
+        ; * 0 on timeout
+        ; * >0 on socket was seen
+        ; * -1 on error
+        TST.L D0
+        BEQ _SocketWaitAsyncWriting_Timeout
+        BMI _SocketWaitAsyncWriting_Error
       MOVE.L (SP)+,D0 ; D0 contains socket again
 
       Dload A4
@@ -1669,6 +1675,7 @@ _SocketWaitAsyncWriting_CheckSockopt:
       TST.L D0
       BEQ _SocketWaitAsyncWriting_Ready
 
+    ; still not ready
     MOVEM.L (SP)+,A3-A4
     MOVE.L #-3,D3
 
@@ -1682,11 +1689,20 @@ _SocketWaitAsyncWriting_Ready:
     RestoreStackFunction
     Ret_Int
 
-_SocketWaitAsyncWriting_Done:
+_SocketWaitAsyncWriting_Error:
       MOVE.L (SP)+,D1
     MOVEM.L (SP)+,A3-A4
 
-    MOVE.L D0,D3
+    MOVE.L #-1,D3
+
+    RestoreStackFunction
+    Ret_Int
+
+_SocketWaitAsyncWriting_Timeout:
+      MOVE.L (SP)+,D1
+    MOVEM.L (SP)+,A3-A4
+
+    MOVEQ #0,D3
 
     RestoreStackFunction
     Ret_Int