Fundamentals of Computer Programming and IT by Pearson

508 Fundamentals of Computer Programming and IT

ios::operator void *()

{

return fail() ? 0 : this;

}

The abov

e function converts an ifstream object into a void pointer. It also invokes ios::fail ()

function, which is as follows:

int fail ()

{

return & (failbit | badbit | hardfail):

}

The above function returns non-zero file when end of file is not encountered. The function returns address

of object using this pointer. Zero is returned when end of file is reached. The while or if statement

checks whether the value is zero or non-zero (address of object ). Here, zero means false and non-zero means

true. The details of the above functions are discussed ...