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problem opening files

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Join Date: Jul 2005

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Jon182

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problem opening files

Feb 13th, 2006

Hey guys I am using code that does the following:

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cin.ignore(); 
cin.getline(file, 250);
 
ifstream test;
 
  test.open (file);
 
	if (test.fail())
		{
		  cout<<"error"<<endl;
 
		  exit(1);
	     }
 
...
cin.ignore(); 
cin.getline(file, 250);

ifstream test;

  test.open (file);

	if (test.fail())
		{
		  cout<<"error"<<endl;

		  exit(1);
	     }

...

The problem is that if a file name is entered that does not exist for example c:\\fred.txt the error message will not appear and the txt file fread will be created, but if I enter "c:\\fred.txt" the code seems to work, but I have created similar code before using cin.getline and the quotes were not needed. Any ideas what I have done wrong?

Thanks.

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Re: problem opening files

Feb 13th, 2006

when you enter the filename from the keyboard do not use double backslash -- double slashes are only needed for string literals in your program. So you should type c:\fred.txt , only one backslash. Reason: the compiler does not interpret anything you enter from the keyboard, it only interprets string literals.

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Jon182

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Re: problem opening files

Feb 13th, 2006

Hi thanks for your reply but when i do this I still have the same problem.

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Re: problem opening files

Feb 13th, 2006

then the problem is elsewhere. try test.is_open() instead of if test.fail(). Use your compiler's debugger and look at what exactly is in the file buffer, or use cout to display it.

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Jon182

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Re: problem opening files

Feb 13th, 2006

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Originally Posted by Ancient Dragon

then the problem is elsewhere. try test.is_open() instead of if test.fail(). Use your compiler's debugger and look at what exactly is in the file buffer, or use cout to display it.

Hi thanks again for your reply, when i use test.is_open() it doesn't find any file even if it exists.