make sure we only show the automatic missing helpers dialog once

src/common/rclconfig.cpp

@@ -24,8 +24,9 @@
 #include <langinfo.h>
 #include <limits.h>
 
-#include <set>
 #include <algorithm>
+#include <list>
+using std::list;
 
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -642,12 +643,13 @@ bool RclConfig::valueSplitAttributes(const string& whole, string& value,
 }
 
 
-string RclConfig::getMissingHelperDesc() const
+bool RclConfig::getMissingHelperDesc(string& out) const
 {
     string fmiss = path_cat(getConfDir(), "missing");
-    string out;
-    file_to_string(fmiss, out);
-    return out;
+    out.clear();
+    if (!file_to_string(fmiss, out))
+	return false;
+    return true;
 }
 
 void RclConfig::storeMissingHelperDesc(const string &s)

src/common/rclconfig.h

@@ -17,22 +17,18 @@
 #ifndef _RCLCONFIG_H_INCLUDED_
 #define _RCLCONFIG_H_INCLUDED_
 
-#include <list>
 #include <string>
 #include <vector>
 #include <set>
 #include <utility>
 #include <map>
-#include <set>
-#ifndef NO_NAMESPACES
-using std::list;
+
 using std::string;
 using std::vector;
 using std::pair;
 using std::set;
 using std::map;
-using std::set;
-#endif
+
 
 #include "conftree.h"
 #include "smallut.h"
@@ -247,7 +243,7 @@ class RclConfig {
     bool mimeViewerNeedsUncomp(const string &mimetype) const;
 
     /** Store/retrieve missing helpers description string */
-    string getMissingHelperDesc() const;
+    bool getMissingHelperDesc(string&) const;
     void storeMissingHelperDesc(const string &s);
 
     /** Find exec file for external filter. cmd is the command name from the