PRODUCT  :  Borland C++                           NUMBER  :  1374
  VERSION  :  All
       OS  :  All
     DATE  :  October 25, 1993                         PAGE  :  1/4

    TITLE  :  An iostream manipulator for pointers




  This example contains two files, IOM_FPTR.H and IOM_FPTR.CPP

  ----BEGIN FILE: IOM_FPTR.H---
  /*
     IOM_FPTR.H:

     fptr() is a manipulator displays a pointer in "xxxx:xxxx"
     format when in 16-bit mode (DOS) and "xxxxxxxx" format
     when in 32-bit mode (OS/2 and NT)

     PURPOSE:

     The fptr() manipulator displays a pointer in the common
     xxxx:xxxx format as provided by the printf() function's
     '%Fp' formatting options.

     In addition to being a useful manipulator, fptr() is an
     example of an output stream manipulator taking one
     argument which is portable across 16 and 32 bit compiler
     boundaries and across compilers which use either macro or
     template implementations of the IOSTREAM manipulator
     machinery.

     USAGE:    char *astring="This is a string";
               int anint;

               cout << "'astring' starts at " << fptr(astring)
                    << endl
                    << "'anint' starts at " << fptr(&anint)
                    << endl;

     NOTES: (1) tested with Borland C++ 3.1 near and far data
                models and Borland C++ for OS/2 1.0.
            (2) for detailed usage information see UNIX System
                V AT&T C++ Language System Release 2.1,
                Library Manual, Chapter 3: Iostream Examples,
                pgs 3-17 through 3-20.

     050693EAS
  */

  #if !defined( __DOS_H )
  #include <dos.h>          // for FP_SEG, FP_OFF













  PRODUCT  :  Borland C++                           NUMBER  :  1374
  VERSION  :  All
       OS  :  All
     DATE  :  October 25, 1993                         PAGE  :  2/4

    TITLE  :  An iostream manipulator for pointers




  #endif  // __DOS_H

  #if !defined( __IOMANIP_H )
  #include <iomanip.h>      // for IOSTREAM basics
  #endif  // __IOMANIP_H

  #if !defined( __IOSTREAM_H )
  #include <iostream.h>     // for manipulator macros/templates
  #endif  // __IOSTREAM_H

  /*-------------------------------------------------------
     fptr - iostream manipulator that takes a pointer and
            reformats to xxxx:xxxx prior to sending out
            ostream 'o'. If invoked from a 32-bit (FLAT)
            program, an unformatted hexadecimal pointer value
            is output.
   */

  ostream& fptr(ostream& o, void *p)
  {
    long f = o.flags();
    cout.fill('0');

  // 16-bit compilers display xxxx:xxxx format.
  #if !defined (__FLAT__)
    o << setw(4) << hex << FP_SEG(p)
      << ":"  << setw(4) << FP_OFF(p);

  // 32-bit compilers (flat) just display 8 hex digits.
  #else
    o << setw(8) << hex << (unsigned) p;
  #endif

    o.flags(f);
    return o;
  }

  /*
   * If 'IOMANIPdeclare' isn't defined, templates are used.
   * Note that Borland compilers use lower case manipulator
   * names for templates.
   */
  #if !defined (IOMANIPdeclare)













  PRODUCT  :  Borland C++                           NUMBER  :  1374
  VERSION  :  All
       OS  :  All
     DATE  :  October 25, 1993                         PAGE  :  3/4

    TITLE  :  An iostream manipulator for pointers




  omanip <void*> fptr(void *p)
  {
    return omanip<void*>(fptr, p);
  }
  #else

  /*
   * If IOMANIPdeclare is defined, macros are used. Note that
   * when macros are used, Borland compilers use upper case
   * names for macros.
   */
  #if !defined (PVOID)
  typedef void *PVOID;
  #endif

  IOMANIPdeclare(PVOID);
  OMANIP(PVOID) fptr(PVOID p)
  {
    return OMANIP(PVOID) (fptr, p);
  }
  #endif // IOMANIPdeclare

  ---END FILE: IOM_FPTR.H-----

































  PRODUCT  :  Borland C++                           NUMBER  :  1374
  VERSION  :  All
       OS  :  All
     DATE  :  October 25, 1993                         PAGE  :  4/4

    TITLE  :  An iostream manipulator for pointers




  ---BEGIN FILE: IOM_FPTR.CPP---
  /*
   * IOM_FPTR.CPP: testbed for fptr() IOSTREAM manipulator
   */

  #include "iom_fptr.h"

  //**************************************************************
  void main(void)
  {
    char *astring="This is a string";
    int anint;

    cout.setf(ios::uppercase);
    cout << "'astring' starts at " << fptr(astring)
         << endl
         << "'anint' starts at " << fptr(&anint)
         << endl;
  } // end of main()

  ---END FILE: IOM_FPTR.CPP----


  DISCLAIMER: You have the right to use this technical information
  subject to the terms of the No-Nonsense License Statement that
  you received with the Borland product to which this information
  pertains.