#include <fstream>
#include <iostream>
 
namespace EdRules {
  using namespace std;
 
  int OPEN_MODE = 0;
 
  void foo(ostream& os)
  {
    switch (os.iword(OPEN_MODE)) {
      case 0: cout << "Binary\n"; break;
      case 1: cout << "Text\n"; break;
    }
  }
}
 
int main()
{
  using namespace std;
  using namespace EdRules;
 
  OPEN_MODE = cout.xalloc();
  cout.iword(OPEN_MODE) = 0;
 
  foo(cout);
 
  cout.iword(OPEN_MODE) = 1;
 
  foo(cout);
}

int main( void )
{
  std::ofstream out( "test.bin", std::ios::binary | std::ios::out | std::ios::trunc );
  const float f1 = 123.456f;
  out.write( reinterpret_cast< const char * >( &f1 ), sizeof( float ) );
  out.close( );
 
  std::ifstream in( "test.bin", std::ios::binary | std::ios::in );
  float f2 = 0.0f;
  in.read( reinterpret_cast< char * >( &f2 ), sizeof( float ) );
  in.close( );
 
  assert( f1 == f2 );
}

int main( void )
{
  std::ofstream out( "test.bin", std::ios::binary | std::ios::out | std::ios::trunc );
  const float f1 = 123.456f;
  const char * c1 = reinterpret_cast< const char * >( &f1 );
  for( size_t i = 0; i < sizeof( float ); ++i ) {
    out.put( c1[ i ] );
  }
  out.close( );
 
  std::ifstream in( "test.bin", std::ios::binary | std::ios::in );
  float f2 = 0.0f;
  char * c2 = reinterpret_cast< char * >( &f2 );
  for( size_t i = 0; i < sizeof( float ); ++i ) {
    c2[ i ] = in.get( );
  }
  in.close( );
 
  assert( f1 == f2 );
}

#include <iostream>
 
float ToFloat(const unsigned char *bytes)
{
  unsigned long temp = 0;
 
  temp |= (bytes[0] & 0xFF) << 24;
  temp |= (bytes[1] & 0xFF) << 16;
  temp |= (bytes[2] & 0xFF) << 8;
  temp |= (bytes[3] & 0xFF) << 0;
 
  return *reinterpret_cast<float*>(&temp);
}
 
unsigned char *FromFloat(float value, unsigned char *bytes)
{
  unsigned long *temp = reinterpret_cast<unsigned long*>(&value);
 
  bytes[0] = static_cast<unsigned char>((*temp >> 24) & 0xFF);
  bytes[1] = static_cast<unsigned char>((*temp >> 16) & 0xFF);
  bytes[2] = static_cast<unsigned char>((*temp >> 8) & 0xFF);
  bytes[3] = static_cast<unsigned char>((*temp >> 0) & 0xFF);
 
  return bytes;
}
 
int main()
{
  using namespace std;
 
  float value = 247.548f;
  unsigned char bytes[4];
 
  cout << fixed << ToFloat(FromFloat(value, bytes)) << '\n';
}