#include <octave/config.h>

#include <iostream.h>

#include <octave/defun-dld.h>
#include <octave/error.h>
#include <octave/oct-obj.h>
#include <octave/pager.h>
#include <octave/symtab.h>
#include <octave/file-ops.h>
#include <octave/file-stat.h>
#include <octave/oct-syscalls.h>
#include <octave/gripes.h>
#include <octave/lo-utils.h>
#include <octave/oct-map.h>
#include <octave/oct-stdstrm.h>
#include <octave/oct-stream.h>
#include <octave/sysdep.h>
#include <octave/syswait.h>
#include <octave/utils.h>
#include <octave/variables.h>

DEFUN_DLD (gpipe, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} address@hidden, @var{err}, @var{msg}] =} gpipe ()\n\
Create a pipe and return the vector @var{file_ids}, which corresponding\n\
to the reading and writing ends of the pipe.\n\
\n\
If successful, @var{err} is 0 and @var{msg} is an empty string.\n\
Otherwise, @var{err} is nonzero and @var{msg} contains a\n\
system-dependent error message.\n\
@end deftypefn") {
  octave_value_list retval;

  retval(2) = std::string ();
  retval(1) = -1.0;
  retval(0) = Matrix ();

  int nargin = args.length ();

  if (nargin == 0) {
      int fid[2];
      double ipipe,opipe;
      std::string msg;

      int status = octave_syscalls::pipe (fid, msg);

      if (status < 0)
	     retval(2) = msg;
      else {
  	    FILE *ifile = fdopen (fid[0], "r");
  	    FILE *ofile = fdopen (fid[1], "w");
  
  	    octave_stream is = octave_istdiostream::create (std::string (), ifile);
  	    octave_stream os = octave_ostdiostream::create (std::string (), ofile);

        //Both of the following approaches yield the same result:
		//The function works fine when invoked from octave command line
		//but gives the wrong answer when invoked from a .m file
		
		//ipipe = fid[0];
		//opipe = fid[1];
		ipipe = (double) is.file_number();
		opipe = (double) os.file_number();

  	    octave_value_list file_ids;
  
        file_ids(3) = ipipe;
  	    file_ids(2) = opipe;
  	    file_ids(1) = octave_stream_list::insert (os);
  	    file_ids(0) = octave_stream_list::insert (is);
  	   
  	    retval(1) = static_cast<double> (status);
        retval(0) = octave_value (file_ids);
	  }
    }
  else
    print_usage ("gpipe");

  return retval;
}