patch: tcl espeak to work under windows

[Jarek Czekalski <jarekczek@xxxxxxxxxxx>]

Implemented 2 workarounds for tcl script in espeak server, so that it 
could be run on Windows.

With this patch emacspeak is ready to be built on Windows. Building is 
not difficult, however suitable libraries and switches must be employed 
to get it working. Binary release and building instructions soon.

Regards
Jarek

Index: servers/espeak
===================================================================
--- servers/espeak	(revision 8407)
+++ servers/espeak	(working copy)
@@ -76,6 +76,7 @@
 set langlabel(0) "english"
 set langcode(0) "en-uk"
 set langcode(current) "en-uk"
+set mswindows [expr { $tcl_platform(platform) == "windows" } ]
 
 # select the next synth language
 proc set_next_lang {say_it} {
@@ -409,12 +410,43 @@
     set tts(last_index) $index
 }
 
+proc stdin_readable_handler {} {
+  global stdin_is_readable
+  global timer_or_stdin_breaks
+  set stdin_is_readable 1
+  set timer_or_stdin_breaks 1
+}
+if $mswindows { fileevent stdin readable stdin_readable_handler }
+
+proc timer_handler {} {
+  global timer_ticks
+  global timer_or_stdin_breaks
+  after 200 timer_handler
+  set timer_ticks 1
+  incr timer_or_stdin_breaks
+}
+if $mswindows { after 0 timer_handler }
+
 proc service {} {
     global tts
+    global stdin_is_readable # used only by mswindows
 
     set talking [speakingP]
+    set stdin_is_readable 0
     while {$talking == 1} {
-        set status   [lsearch [select [list  stdin]  {} {} 0.02] stdin]
+        if $::mswindows {
+            # need to workaround lack of "select stdin" on windows
+            # set status to 1 if input is available at stdin
+            # if input is not available, timer will cause an exit from vwait
+            set status -1
+            vwait timer_or_stdin_breaks
+            if { $stdin_is_readable > 0 } {
+                set status 1
+            }
+        } else {
+            set status   [lsearch [select [list  stdin]  {} {} 0.02] stdin]
+        }
+
         if { $status >= 0} {
             set tts(talking?) 0
             set talking 0
@@ -528,9 +560,14 @@
 
 #Start the main command loop:
 
-commandloop 
+if $mswindows {
+  # there is a bug on windows, interactive -on does not work
+  # https://sourceforge.net/p/tclx/bugs/81/
+  commandloop -interactive off
+} else {
+  commandloop
+}
 
-
 # }}}
 # {{{ Emacs local variables