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[raven.mp4]

Hi. Is there any function like getline which loads specified line from
a text file? Something like getline(myfile, line, 10); where 10 means
10th line in the file.

 

[Victor Bazarov]

Hi. Is there any function like getline which loads specified line from
a text file? Something like getline(myfile, line, 10); where 10 means
10th line in the file.

No. It's too easy to write using 'getline' and 'ignore' to bother
putting it in the library, methinks.

V

 

[raven.mp4]

No. It's too easy to write using 'getline' and 'ignore' to bother
putting it in the library, methinks.

V

So how to code it?

 

[Victor Bazarov]

So how to code it?

Something like

std::istream& skip_lines(std::istream& is, std::size_t n)
{
while (is && n--)
is.ignore(
std::numeric_limits<std::istream::streamsize>::max(),
'\n');
return is;
}

...
std::ifstream myfile; // and open it
if (skip_lines(myfile, 10))
getline(myfile, line);

V

 

[Jerry Coffin]

Hi. Is there any function like getline which loads specified line from
a text file? Something like getline(myfile, line, 10); where 10 means
10th line in the file.

No -- to do something like that, you'd need an index of the text file
telling where each line begins. You can do that, but it's not built in.