fix NaN and long strings

ca

@@ -2,12 +2,12 @@
 
 # ca* by Dirk Zimoch
 # $Source: /cvs/G/EPICS/App/scripts/ca,v $
-# $Date: 2015/05/18 07:09:44 $
+# $Date: 2015/05/18 07:56:05 $
 
 regsub -all {\$} {ca* by Dirk Zimoch
 $Source: /cvs/G/EPICS/App/scripts/ca,v $
-$Revision: 1.29 $
-$Date: 2015/05/18 07:09:44 $} {} version
+$Revision: 1.30 $
+$Date: 2015/05/18 07:56:05 $} {} version
 
 package require Tclx
 package require Epics
@@ -125,8 +125,11 @@ proc formatval {channel {value {}} {sevr {}} {stat {}} {time {}}} {
             set time $TIME
         }
         if {$TYPE == "DBF_STRING" && [string length $value] == 39} {
-            puts "reread $channel as $channel$"
-            set value [pvget $channel$]
+            # long string: try to re-read as array of char
+            set field [file extension $channel]
+            if {$field != "" && $field != ".VAL"} {
+                catch {set value [pvget $channel$]}
+            }
         }
         catch {
             set null 0
@@ -156,10 +159,14 @@ proc formatval {channel {value {}} {sevr {}} {stat {}} {time {}}} {
         }
         foreach val $value {
             if [info exists PREC] {
-                if {$PREC < 0} {
-                    set val [format "%.[expr -$PREC]e" $val]
-                } else {
-                    set val [format "%.${PREC}f" $val]
+                if [catch { # new Tcl fails on NaN. Suck.
+                    if {$PREC < 0} {
+                        set val [format "%.[expr -$PREC]e" $val]
+                    } else {
+                        set val [format "%.${PREC}f" $val]
+                    }
+                }] {
+                    set val "NaN"
                 }
             }
             if {$TYPE == "DBF_ENUM" && \