Asynchronous agent requests on Windows. Actually, I've kept the

ability to do synchronous ones as well, because PSCP and PSFTP don't
really need async ones and it would have been a serious pain to
implement them. Also, Pageant itself when run as a client of its
primary instance doesn't benefit noticeably from async agent
requests.

[originally from svn r3154]

winstuff.h

@@ -319,4 +319,16 @@ void EnableSizeTip(int bEnable);
 struct unicode_data;
 void init_ucs(Config *, struct unicode_data *);
 
+/*
+ * pageantc.c needs to schedule callbacks for asynchronous agent
+ * requests. This has to be done differently in GUI and console, so
+ * there's an exported function used for the purpose.
+ * 
+ * Also, we supply FLAG_SYNCAGENT to force agent requests to be
+ * synchronous in pscp and psftp.
+ */
+void agent_schedule_callback(void (*callback)(void *, void *, int),
+			     void *callback_ctx, void *data, int len);
+#define FLAG_SYNCAGENT 0x1000
+
 #endif