WSA functions should be marked SetLastError where appropriate

[ansteele]

Hello,

Many WSA functions call WSASetLastError as a means of returning error information.
I believe WSASet/GetLastError is simply an alias of the regular Set/GetLastError therefore it would make sense that WSA functions be marked as SetLastError = true.

Many thanks

[riverar]

I was suspicious of this, so took a peek under the hood and, well, see for yourself. 😂

int __stdcall WSAGetLastError()
{
  return GetLastError();
}

void __stdcall WSASetLastError(int iError)
{
  SetLastError(iError);
}

[ChrisDenton]

Aye, see also WSAWaitForMultipleEvents, WSASetEvent and probably others too. On the one hand it's possible they'd want to reserve the right to change it again the future. On the other hand I wouldn't be surprised if people have come to rely on it.

[riverar]

Thankfully only NEMA 10-30 folks use winsock. 😂

[riverar]

For those interested, I dug through some very old documentation and here are some clarifying details:

The use of the WSAGetLastError() function to retrieve the last error code, rather than relying on a global error variable (cf. errno), is required in order to provide compatibility with future multi-threaded environments.

Note that in a Win16 environment WSAGetLastError() is used to retrieve only Windows Sockets API errors. In a Win32 environment, WSAGetLastError() will invoke GetLastError(), which is used to retrieve the error status for all Win32 API functions on a per-thread basis. For portability, an application should use WSAGetLastError() immediately after the Windows Sockets API function which failed.