Re: ifstream ofstream ?

From:

Goran <goran.pusic@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Fri, 9 Sep 2011 03:56:46 -0700 (PDT)

Message-ID:

<82c9e0b4-cd70-49ef-a2c5-976dbcaa88aa@o26g2000vbi.googlegroups.com>

On Sep 9, 12:16 pm, Asger-P <j...@asger-p.dk> wrote:

Hi

I never used ifstream and ofstream before, so I searched a little
and made this little function, for removing BOM's in php files.
It works fine, I just want to make sure that I'm doing it right.

void __fastcall removeBOM(char* fileName)
{
    ifstream ifile(fileName, ios::in | ios::binary | ios::nocreate);
    if( ! ifile )
    return;

    unsigned char Bom[3];
    ifile.seekg( 0 );
    ifile.read ( Bom, 3 );

    if( Bom[0] == 0xEF && Bom[1] == 0xBB && Bom[2] == 0xB=

F )

    {
       bool Done = false;
       string tmpFile = fileName;
       tmpFile += "tmptmp";

       ofstream ofile( tmpFile.c_str() );
       if( ofile )
       {
          ofile << ifile.rdbuf();
          ofile.close();
          Done = true;
       }
       ifile.close();

       //renaming and deleting files

       return;
    }

    ifile.close();

}

in particular this line:

if( ! ifile )

isn't that always true on an refference ?

First off: what reference?

Second, try this:

class test
{
};

test t;
test& r = t;
if (r) // doesn't compile
{
}

I suggest to step through that "if" (not "step over") with your
debugger and think about what you're seeing. (I am not trying to be
facetious, I am certain you'll learn something this way)

Goran.