Many people suppose that C/C++ is dead with the advent of Java. However, C/C++ applications are still continued to be developed and deployed. Several applications such as MySQL, PhP, Java, etc. are still developed and deployed in C/C++. With DTrace, the possibilities of tracing applications and gaining an overview in a "non-destructive" way, has opened the opportunities for its usage on production quality systems. From a developer perspective, you could incrementally introduce DTrace probes in the critical paths of your code. Typically, 20% of a software's lifetime lies in the developmental phase and 80% of it is in maintainence.

To ease the debugging of applications, be it on a development system or on a production machine, DTrace offers you wide possibilities. However, the problem is not that simple. When considering C/C++, the way DTrace handles them differently. This is because of the name-mangling phenomenon, that flattens the namespaces of C++ applications. Why should this be done?

UNIX is a flat world too. UNIX understands flat namespaces and was developed or is still developed with the C-language and as a result has a flat namespace. C++ offers the hierarchial namespaces, whereby its possible to organize information in a hierarchial way. UNIX does not understand this hierarchy. Thats a problem! C++ overcomes this by flattening the namespace that makes UNIX happy. This phenomenon is called the name-decoration or name-mangling or namespace mangling and so on.

Let me illustrate this with a small program, written in C and compiled with the Sun Studio compiler ( C & C++ compilers). Lets us call this program hallo.c which has nothing spectacular, but has a simple function, void printHallo(int), taking an integer argument. This function prints the word, "Hallo", n-times depending upon the argument you pass to this function. The program listing is as follows:

meson:/export/home/mithun/USDT >more hallo.c
#include

void printHallo(int);

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