Hello, pulsar!

In the tradition of computing language tutorials, the following example provides a simple introduction to the PSRCHIVE library. 
#include "Pulsar/Archive.h"

#include <iostream>

using namespace std;

int main (int argc, char** argv)
{
  if (argc < 2) {
    cerr << "Please specify a filename" << endl;
    return -1;
  }

  Reference::To<Pulsar::Archive> archive;

  archive = Pulsar::Archive::load (argv[1]);

  cout << "Hello, PSR " << archive->get_source() << "!" << endl;

  return 0;
}
Although this is one of the least useful programs that can be written, it includes the basic components of every PSRCHIVE program:

#include "Pulsar/Archive.h"
This header file defines the Pulsar::Archive class; it also includes the headers of all other class definitions required in order to define this class.

Reference::To<Pulsar::Archive> archive;
The Reference::To template class is a smart pointer. It will automatically destroy an object if it is the last smart pointer that refers to that object when it is reset. Also, if the object to which a Reference::To points is deleted, the reference will be automatically invalidated. Note that it is not necessary to delete an object to which a Reference::To smart pointer points.

archive = Pulsar::Archive::load (argv[1]);
This line loads the data from the filename specified by the first argument to the program. Pulsar::Archive::load is known as a factory; it returns a newly constructed instance of the appropriate derived class (e.g. Pulsar::FITSArchive, Pulsar::TimerArchive, or Pulsar::EPNArchive) according to the format of the archive data in the specified file.

cout << "Hello, PSR " << archive->get_source() << "!" << endl;
This line prints the name of the source loaded from the specified file. Notice that the program need know neither what type of file was loaded, nor what this attribute would have been named in the header of this file. The Pulsar::Archive base class defines a common interface to all file formats.