The system() function (declared in ) launches another program from the current program. As opposed to what most users think, it doesn’t return the exit code of the launched process. Instead, it returns the exit code of the shell that launches the process in question. Consider the following example:

 int main(){ int stat = system("winword.exe"); //launch Word and wait                                    // until the user closes it}

When the system() call returns, the value assigned to stat is the exit code of the shell process that in turn launches Word, not Word