Changes to Tcl and Threads between r2 and r4
'''Using [Threads] and [Tcl]'''
Some consolidated rules for embedding [Tcl] in a threaded application (from http://wiki.tcl.tk/1339)
* You can NEVER use the same interpreter from more than one thread
* If you only have one Tcl Interpreter:
** You can use either Unthreaded or Threaded Tcl
** No ''Big Global Mutex'' [Big Global Mutex] is required for Unthreaded Tcl Build (Never required for Threaded Tcl build)
** No ''Big Global Mutex'' is required for Unthreaded Tcl Build (Never required for Threaded Tcl build)
* If you have Multiple Tcl Interpreters:
** If you are using an Unthreaded Tcl ''Big Global Mutex'' [Big Global Mutex] is required for '''ALL''' calls to functions in libtcl
** If you are using an Unthreaded Tcl ''Big Global Mutex'' is required for '''ALL''' calls to functions in libtcl
** If you are using a Threaded Tcl, no mutex locks are required
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A [Protothreads] Tcl example:
http://www.rkeene.org/projects/info/resources/threads/test2-pt.c
Only in r2
Only in r4 --> Modified slightly between r2 and r4