diff --git a/contrib/win32/win32compat/w32fd.c b/contrib/win32/win32compat/w32fd.c
index 080714242..35a5b9646 100644
--- a/contrib/win32/win32compat/w32fd.c
+++ b/contrib/win32/win32compat/w32fd.c
@@ -88,6 +88,19 @@ fd_table_initialize()
 {
 	struct w32_io *pio;
 	HANDLE wh;
+	char *stdio_mode_env;
+	int stdio_mode = NONSOCK_SYNC_FD;
+
+	stdio_mode_env = getenv("OPENSSH_STDIO_MODE");
+	if (stdio_mode_env != NULL) {
+		if (strcmp(stdio_mode_env, "sock") == 0)
+			stdio_mode = SOCK_FD;
+		else if (strcmp(stdio_mode_env, "nonsock") == 0)
+			stdio_mode = NONSOCK_FD;
+		else if (strcmp(stdio_mode_env, "nonsock_sync") == 0)
+			stdio_mode = NONSOCK_SYNC_FD;
+	}
+
 	/* table entries representing std in, out and error*/
 	DWORD wh_index[] = { STD_INPUT_HANDLE , STD_OUTPUT_HANDLE , STD_ERROR_HANDLE };
 	int fd_num = 0;
@@ -104,7 +117,7 @@ fd_table_initialize()
 				return -1;
 			}
 			memset(pio, 0, sizeof(struct w32_io));
-			pio->type = NONSOCK_SYNC_FD;
+			pio->type = stdio_mode;
 			pio->handle = wh;
 			fd_table_set(pio, fd_num);
 		}