Cygwin: pipe: Avoid false EOF while reading output of C# programs.

- If output of C# program is redirected to pipe, pipe reader falsely
  detects EOF. This happens after overhaul of pipe implementation.
  This patch fixes the issue.

Addresses:
  https://cygwin.com/pipermail/cygwin/2021-November/249777.html

winsup/cygwin/fhandler_pipe.cc

@@ -393,7 +393,8 @@ fhandler_pipe::raw_read (void *ptr, size_t& len)
 	    }
 	}
 
-      if (nbytes_now == 0 || status == STATUS_BUFFER_OVERFLOW)
+      if ((nbytes_now == 0 && !NT_SUCCESS (status))
+	  || status == STATUS_BUFFER_OVERFLOW)
 	break;
     }
   ReleaseMutex (read_mtx);

winsup/cygwin/release/3.3.2

@@ -8,3 +8,7 @@ Bug Fixes
   Addresses: https://sourceware.org/pipermail/newlib/2021/018626.html
 
 - Fix a permission problem when writing ACLs on Samba.
+
+- Fix the issue that pipe reader falsely detects EOF if the output of
+  the C# program is redirected to the pipe.
+  Addresses: https://cygwin.com/pipermail/cygwin/2021-November/249777.html