🚀 go-pugleaf

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From: laurenz@juno.neuroinformatik.ruhr-uni-bochum.de (Laurenz Wiskott)
Subject: gcc-2.2.2 libg++-2.2 stream bugs
To: bug-gcc@prep.ai.mit.edu
Cc: neef@neuroinformatik.ruhr-uni-bochum.de,
        laurenz@neuroinformatik.ruhr-uni-bochum.de
Date: Fri, 9 Oct 92 10:07:15 +0100

	Dear 'GNU',

I've great respect for your Organization and like your software very
much. Many thanks for all that.

We are just changing from the AT&T C++ compiler to your gcc-2.2.2 with
the libg++-2.2. And the bugs changes also. I think I've found at least
one bug concerning the file streams. Here follows a simple example:

- ----------------------------------------------------------------------

#include <fstream.h>

main()
{
  // the test files test1 and test2 do not yet exist ;

  // this behaves as expected ;
  ifstream ifile;
  ifile.open("test1",ios::in);
  cerr << ifile.good() << flush;
  ofstream ofile;
  ofile.open("test1",ios::out);   // the test1 file will be created here ;
  ofile << "data1" << flush;
  cerr << ofile.good() << flush;

  // but it is not possible to open a fstream 
  // in order to write something onto a file 
  // after you have tried to open it fruitless for a read access ;
  fstream iofile;
  iofile.open("test2",ios::in);
  cerr << iofile.good() << flush;
  iofile.close();              // even with a close() command ;
  iofile.open("test2",ios::out); 
  cerr << iofile.fail() << iofile.good() << flush; // output: 40
  iofile << "data2" << flush;   // no data in the test2 file ;

  // but it works with the AT&T compiler ;
};

- ----------------------------------------------------------------------

The second is more an uncomfortable feature than really a bug I think.
Consider the following two programs.

- ----------------------------------------------------------------------

#include <stream.h>

typedef char arrType;
#define arrSize 16

main()
{
  arrType arr[arrSize];
  for (int i=0; i<arrSize; i++)
    arr[i]=(arrType)i;
  cout.write((char *)arr,sizeof(arrType)*arrSize);
//  cout.flush();
}

- ----------------------------------------------------------------------

#include <stream.h>

typedef char arrType;
#define arrSize 16

main()
{
  arrType arr[arrSize];
  cin.read((char*)arr,sizeof(arrType)*arrSize);
  for (int i=0; i<arrSize; i++)
    cerr << i << " : " << float(arr[i]) << "\n";
}

- ----------------------------------------------------------------------

Compile it to get the executables 'out' and 'in' and pipe the result
of the first to the second: out|in. You can do it with or without the
flush command. The flush seems necessary but as I think it would be
more comfortable if it would not. 


	Kind regards, Laurenz Wiskott.



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