Problem opening ifstream twice ...

[Joe]

Hello -

I use a ifstream to open a file in my code. I read through it using
getline() and then I close() it. Later in the code I try to open the
same file but it fails. Here is the code:

ifstream InputFile;

char Line[MAXcharLine + 1]; // MAXcharLine = 512

InputFile.open("XXX.dat");

if (InputFile == NULL)
{
// ERROR
}

while (InputFile.getline(Line, MAXcharLine))
{
// DO STUFF
}

InputFile.close();

....

InputFile.open("XXX.dat")

if (InputFile == NULL)
{
// This is where the code fails!
}

What is wrong that it doesn't work? If I don't do the getline() then
it works fine.

Thanks a lot,
Joe

 

[Kamil Burzynski]

InputFile.close();

do InputFile.clear(); here.

 

[Sharad Kala]

Hello -

I use a ifstream to open a file in my code. I read through it using
getline() and then I close() it. Later in the code I try to open the
same file but it fails. Here is the code:

ifstream InputFile;

char Line[MAXcharLine + 1]; // MAXcharLine = 512

InputFile.open("XXX.dat");

if (InputFile == NULL)
{
// ERROR
}

while (InputFile.getline(Line, MAXcharLine))
{
// DO STUFF
}

InputFile.close();

...

InputFile.open("XXX.dat")

if (InputFile == NULL)
{
// This is where the code fails!
}

What is wrong that it doesn't work? If I don't do the getline() then
it works fine.

The error bit in stream is set after your first file has been read completely
till eof.
This is not cleared automatically and is the duty of the programmer.
So call the clear function on the stream and it should be ok.

Best wishes,
Sharad