Learned more about gdb's dprintf. Made some changes.

tests/hellodprintf/hellodprintf_call_channel.cpp

@@ -0,0 +1,25 @@
+#include <string>
+#include <iostream>
+#include <iomanip>
+#include <stdio.h>
+#include <stdarg.h>
+
+int main (int argc, char** argv) {
+
+    int count = 10;
+    int nfact = 1;
+    int n;
+
+    // Add the 'dprintf' function to the program's symbol
+    // table. So we can use it for gdb's 'dprintf' breakpoints.
+    dprintf(1, " C++ loop\n");
+
+    for (n=1; n<=count; n++) {
+        nfact = nfact * n;
+        // printing the value of n and its factorial
+        std::cout << std::setw(12)  << n << std::setw(14) << nfact << std::endl;
+    }
+
+    return 0;
+}
+