10 PRINT "HELLO WORLD"  20 END

  program Hello(input, output)    begin      writeln('Hello World')    end.

  (defun hello    (print      (cons 'Hello (list 'World))))

  #include   void main(void)  {    char *message[] = {"Hello ", "World"};    int i;    for(i = 0; i < 2; ++i)      printf("%s", message[i]);    printf("\n");  }

  #include   #include   class string  {  private:    int size;    char *ptr;  string() : size(0), ptr(new char[1]) { ptr[0] = 0; }    string(const string &s) : size(s.size)    {      ptr = new char[size + 1];      strcpy(ptr, s.ptr);    }    ~string()    {      delete [] ptr;    }    friend ostream &operator <<(ostream &, const string &);    string &operator=(const char *);  };  ostream &operator<<(ostream &stream, const string &s)  {    return(stream << s.ptr);  }  string &string::operator=(const char *chrs)  {    if (this != &chrs)    {      delete [] ptr;     size = strlen(chrs);      ptr = new char[size + 1];      strcpy(ptr, chrs);    }    return(*this);  }  int main()  {    string str;    str = "Hello World";    cout << str << endl;    return(0);  }

  [  uuid(2573F8F4-CFEE-101A-9A9F-00AA00342820)  ]  library LHello  {      // bring in the master library      importlib("actimp.tlb");      importlib("actexp.tlb");      // bring in my interfaces      #include "pshlo.idl"      [      uuid(2573F8F5-CFEE-101A-9A9F-00AA00342820)      ]      cotype THello   {   interface IHello;   interface IPersistFile;   };  };  [  exe,  uuid(2573F890-CFEE-101A-9A9F-00AA00342820)  ]  module CHelloLib  {      // some code related header files      importheader();      importheader();      importheader();      importheader("pshlo.h");      importheader("shlo.hxx");      importheader("mycls.hxx");      // needed typelibs      importlib("actimp.tlb");      importlib("actexp.tlb");      importlib("thlo.tlb");      [      uuid(2573F891-CFEE-101A-9A9F-00AA00342820),      aggregatable      ]      coclass CHello   {   cotype THello;   };  };  #include "ipfix.hxx"  extern HANDLE hEvent;  class CHello : public CHelloBase  {  public:      IPFIX(CLSID_CHello);      CHello(IUnknown *pUnk);      ~CHello();      HRESULT  __stdcall PrintSz(LPWSTR pwszString);  private:      static int cObjRef;  };  #include   #include   #include   #include   #include "thlo.h"  #include "pshlo.h"  #include "shlo.hxx"  #include "mycls.hxx"  int CHello::cObjRef = 0;  CHello::CHello(IUnknown *pUnk) : CHelloBase(pUnk)  {      cObjRef++;      return;  }  HRESULT  __stdcall  CHello::PrintSz(LPWSTR pwszString)  {      printf("%ws", pwszString);      return(ResultFromScode(S_OK));  }  CHello::~CHello(void)  {  // when the object count goes to zero, stop the server  cObjRef--;  if( cObjRef == 0 )      PulseEvent(hEvent);  return;  }  #include   #include   #include "pshlo.h"  #include "shlo.hxx"  #include "mycls.hxx"  HANDLE hEvent;   int _cdecl main(  int argc,  char * argv[]  ) {  ULONG ulRef;  DWORD dwRegistration;  CHelloCF *pCF = new CHelloCF();  hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);  // Initialize the OLE libraries  CoInitializeEx(NULL, COINIT_MULTITHREADED);  CoRegisterClassObject(CLSID_CHello, pCF, CLSCTX_LOCAL_SERVER,      REGCLS_MULTIPLEUSE, &dwRegistration);  // wait on an event to stop  WaitForSingleObject(hEvent, INFINITE);  // revoke and release the class object  CoRevokeClassObject(dwRegistration);  ulRef = pCF->Release();  // Tell OLE we are going away.  CoUninitialize();  return(0); }  extern CLSID CLSID_CHello;  extern UUID LIBID_CHelloLib;  CLSID CLSID_CHello = { /* 2573F891-CFEE-101A-9A9F-00AA00342820 */      0x2573F891,      0xCFEE,      0x101A,      { 0x9A, 0x9F, 0x00, 0xAA, 0x00, 0x34, 0x28, 0x20 }  };  UUID LIBID_CHelloLib = { /* 2573F890-CFEE-101A-9A9F-00AA00342820 */      0x2573F890,      0xCFEE,      0x101A,      { 0x9A, 0x9F, 0x00, 0xAA, 0x00, 0x34, 0x28, 0x20 }  };  #include   #include   #include   #include   #include   #include "pshlo.h"  #include "shlo.hxx"  #include "clsid.h"  int _cdecl main(  int argc,  char * argv[]  ) {  HRESULT  hRslt;  IHello        *pHello;  ULONG  ulCnt;  IMoniker * pmk;  WCHAR  wcsT[_MAX_PATH];  WCHAR  wcsPath[2 * _MAX_PATH];  // get object path  wcsPath[0] = '\0';  wcsT[0] = '\0';  if( argc > 1) {      mbstowcs(wcsPath, argv[1], strlen(argv[1]) + 1);      wcsupr(wcsPath);      }  else {      fprintf(stderr, "Object path must be specified\n");      return(1);      }  // get print string  if(argc > 2)      mbstowcs(wcsT, argv[2], strlen(argv[2]) + 1);  else      wcscpy(wcsT, L"Hello World");  printf("Linking to object %ws\n", wcsPath);  printf("Text String %ws\n", wcsT);  // Initialize the OLE libraries  hRslt = CoInitializeEx(NULL, COINIT_MULTITHREADED);  if(SUCCEEDED(hRslt)) {      hRslt = CreateFileMoniker(wcsPath, &pmk);      if(SUCCEEDED(hRslt))   hRslt = BindMoniker(pmk, 0, IID_IHello, (void **)&pHello);      if(SUCCEEDED(hRslt)) {   // print a string out   pHello->PrintSz(wcsT);   Sleep(2000);   ulCnt = pHello->Release();   }      else   printf("Failure to connect, status: %lx", hRslt);      // Tell OLE we are going away.      CoUninitialize();      }  return(0);  }

  #!/usr/local/bin/perl  $msg="Hello, world.\n";  if ($#ARGV >= 0) {    while(defined($arg=shift(@ARGV))) {      $outfilename = $arg;      open(FILE, ">" . $outfilename) || die "Can't write $arg: $!\n";      print (FILE $msg);      close(FILE) || die "Can't close $arg: $!\n";    }  } else {    print ($msg);  }  1;

  #include   #define S "Hello, World\n"  main(){exit(printf(S) == strlen(S) ? 0 : 1);}

  % cc -o a.out ~/src/misc/hw/hw.c  % a.out

  % echo "Hello, world."

  10 PRINT "HELLO WORLD"  20 END

  mail -s "Hello, world." bob@b12  Bob, could you please write me a program that prints "Hello, world."?  I need it by tomorrow.  ^D

  % zmail jim  I need a "Hello, world." program by this afternoon.

  % letter  letter: Command not found.  % mail  To: ^X ^F ^C  % help mail  help: Command not found.  % damn!  !: Event unrecognized  % logout