Megatest

	     (target   (common:args-get-target))
	     (runname  (or (args:get-arg "-runname")
			   (args:get-arg ":runname")
			   (getenv "MT_RUNNAME")))
	     (fulldir  (conc linktree "/"
			     target "/"
			     runname)))
	(debug:print-info 0 "Have -runtests with target=" target ", runname=" runname ", fulldir=" fulldir ", testpatt=" (or (args:get-arg "-testpatt") "%"))
	(if (and linktree (file-exists? linktree)) ;; can't proceed without linktree
	    (begin

	      (if (not (file-exists? fulldir))
		  (create-directory fulldir #t)) ;; need to protect with exception handler 
	      (if (and target
		       runname
		       (file-exists? fulldir))
		  (let ((tmpfile  (conc fulldir "/.megatest.cfg." (current-seconds)))
			(targfile (conc fulldir "/.megatest.cfg-"  megatest-version "-" megatest-fossil-hash))
			(rconfig  (conc fulldir "/.runconfig." megatest-version "-" megatest-fossil-hash)))
		    (if (file-exists? rconfig) ;; only cache megatest.config AFTER runconfigs has been cached
			(begin
			  (debug:print-info 0 "Caching megatest.config in " fulldir "/.megatest.cfg")
			  (configf:write-alist *configdat* tmpfile)
			  (system (conc "ln -sf " tmpfile " " targfile))))
		    )))))))


;; set up the very basics needed for doing anything here.
;;
(define (launch:setup-old #!key (force #f))
  ;; would set values for KEYS in the environment here for better support of env-override but 
  ;; have chicken/egg scenario. need to read megatest.config then read it again. Going to 
  ;; pass on that idea for now
  ;; special case
  (if (or force (not (hash-table? *configdat*)))  ;; no need to re-open on every call
      (begin
	(set! *configinfo* (or (if (get-environment-variable "MT_CMDINFO") ;; we are inside a test - do not reprocess configs
				   (let ((alistconfig (conc (get-environment-variable "MT_LINKTREE") "/"
							    (get-environment-variable "MT_TARGET")   "/"
							    (get-environment-variable "MT_RUNNAME")  "/"
							    ".megatest.cfg-"  megatest-version "-" megatest-fossil-hash)))
				     (if (file-exists? alistconfig)
					 (list (configf:read-alist alistconfig)
					       (get-environment-variable "MT_RUN_AREA_HOME"))
					 #f))
				   #f) ;; no config cached - give up
			       (let ((runname (or (args:get-arg "-runname")(args:get-arg ":runname"))))
				 (if runname (setenv "MT_RUNNAME" runname))
				 (find-and-read-config 
				  (if (args:get-arg "-config")(args:get-arg "-config") "megatest.config")
				  environ-patt: "env-override"
				  given-toppath: (get-environment-variable "MT_RUN_AREA_HOME")
				  pathenvvar: "MT_RUN_AREA_HOME"))))
	(set! *configdat*  (if (car *configinfo*)(car *configinfo*) #f))
	(set! *toppath*    (if (car *configinfo*)(cadr *configinfo*) #f))
	(let* ((tmptransport (configf:lookup *configdat* "server" "transport"))
	       (transport    (if tmptransport (string->symbol tmptransport) 'http)))
	  (if (member transport '(http rpc nmsg))
	      (set! *transport-type* transport)
	      (begin
		(debug:print 0 "ERROR: Unrecognised transport " transport)
		(exit))))
	(let ((linktree (configf:lookup *configdat* "setup" "linktree"))) ;; link tree is critical
	  (if linktree
	      (if (not (file-exists? linktree))
		  (begin
		    (handle-exceptions
		     exn
		     (begin
		       (debug:print 0 "ERROR: Something went wrong when trying to create linktree dir at " linktree)
		       (debug:print 0 " message: " ((condition-property-accessor 'exn 'message) exn))
		       (exit 1))
		     (create-directory linktree #t))))
	      (begin
		(debug:print 0 "ERROR: linktree not defined in [setup] section of megatest.config")
		(exit 1)))
	  (if linktree
	      (let ((dbdir (conc linktree "/.db")))
		(handle-exceptions
		 exn
		 (begin
		   (debug:print 0 "ERROR: failed to create the " dbdir " area for your database files")
		   (debug:print 0 " message: " ((condition-property-accessor 'exn 'message) exn)))
		 (if (not (directory-exists? dbdir))(create-directory dbdir)))
		(setenv "MT_LINKTREE" linktree))
	      (begin
		(debug:print 0 "ERROR: linktree is required in your megatest.config [setup] section")
		(exit 1)))
	  (if (and *toppath*
		   (directory-exists? *toppath*))
	      (setenv "MT_RUN_AREA_HOME" *toppath*)
	      (begin
		(debug:print 0 "ERROR: failed to find the top path to your Megatest area.")
		(exit 1)))
	  )))
  *toppath*)

;; gather available information, if legit read configs in this order:
;;
;;   if have cache;
;;      read it a return it
;;   else
;;     megatest.config     (do not cache)