10 PRINT "HELLO WORLD"
20 END

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

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

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

#include <iostream.h>
#include <string.h>
class string
{
private:
   int size;
   char *ptr;
public:
   string() : size(0), ptr(new char('\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(void)
{
   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("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 "thlo.h"
#include "pshlo.h"
#include "shlo.hxx"
#include "mycls.hxx"
int CHello::cObjRef = 0;
CHello::CHello(IUnknown *pUnk) : CHelloBase(pUnk)
{
   cObjRef++;
}
HRESULT  __stdcall CHello::PrintSz(LPWSTR pwszString)
{
   printf("%ws\n", pwszString);
   return ResultFromScode(S_OK);
}
CHello::~CHello()
{
   // when the object count goes to zero, stop the server
   cObjRef--;
   if (cObjRef == 0)
     PulseEvent(hEvent);
}
#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 "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\n", 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 <stdio.h>
#define S "Hello, World\n"
main(){exit(printf(S) == strlen(S) ? 0 : 1);}

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

% cat
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.

% 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

42

<p>Hello World</p>