add comments explaining why '-L' works; add NEWS blurb too

2 files changed, 10 insertions, 2 deletions

diff --git a/NEWS b/NEWS
index be56757d..5036cebb 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,12 @@
 * What's new
 
+- Probe listing mode is improved: "-L" lists available script-level variables
+
+     % stap -L 'syscall.*open*'
+     syscall.mq_open name:string name_uaddr:long filename:string mode:long u_attr_uaddr:long oflag:long argstr:string
+     syscall.open name:string filename:string flags:long mode:long argstr:string
+     syscall.openat name:string filename:string flags:long mode:long argstr:string
+
 - All user-space-related probes support $PATH-resolved executable
   names, so
 
diff --git a/main.cxx b/main.cxx
index 83afb913..5d0739eb 100644
--- a/main.cxx
+++ b/main.cxx
@@ -180,10 +180,11 @@ printscript(systemtap_session& s, ostream& o)
           if (seen.find (pp) == seen.end())
             {
               o << pp;
+              // This list will be empty unless s.unoptimized = true -- i.e., -L mode
               for (unsigned j=0; j<p->locals.size(); j++)
 	            {
       		      o << " ";
-       	      vardecl* v = p->locals[j];
+                      vardecl* v = p->locals[j];
 		      v->printsig (o);
 		    }
 	      o << endl;
@@ -587,7 +588,7 @@ main (int argc, char * const argv [])
           break;
 
         case 'L':
-          s.unoptimized = true;
+          s.unoptimized = true; // This causes retention of variables for listing_mode
 
         case 'l':
 	  s.suppress_warnings = true;