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algorithmwgetresume

Wget resume algorithm

I've noticed that resuming an interrupted download with wget -c is very fast and very reliable.

Does wget use any algorithm to resume the download, or does it simply compare sizes and appends to the existing file?

Solution

  • Does this answer help ?

    http://www.ale.org/pipermail/ale/2005-November/082061.html

    Wget looks at the file size and assumes retrieval should continue with the next byte past the end of the downloaded file segment. Wget then sends an http 'range' header field to the server to tell it where to restart the retrieval.