Making progress on util::dprintf

luprex/cpp/core/util.hpp

@@ -357,6 +357,22 @@ inline eng::string ss(const ARGS & ... args) {
     return oss.str();
 }
 
+
+
+// dprintf
+//
+// Send a debugging message to somewhere that it can be seen. This routine
+// initially just sends output to stderr.  But it can be hooked to send output
+// somewhere else, like to a debug output window.
+//
+// The hook function must be a function that accepts a single line of text.  The
+// hook function will always be passed one line, consisting of printable
+// characters only.  There will be no control characters.  The newline is
+// implied. 
+//
+void dprintf(const char *format, ...);
+void hook_dprintf(void (*func)(const char *oneline));
+
 // A better API than std::setfill, std::hex, std::setw, std::setprecision
 //
 // Usage examples: