It doesn't print any content because the while at the top exits immediately.

The while at the top exits immediately because you opened the file for appending (>>) instead of for reading (<).

I think I see what you intend to do: you want to use the file as a queue, where you append new URLs to the end, and read unprocessed ones from the start (middle).

A file is the wrong type of a datastructure for that.

You could use an array, where you push new URLs in at one end, and shift them out at the other.

Of course, in a real webcrawler, that array is going to get rather large.

In reply to Re: Re: Re: Useless use of substr in void context by Anonymous Monk
in thread Useless use of substr in void context by mkurtis

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