wget(1) --convert-links
The non-interactive network downloader
-k
--convert-links
    After the download is complete, convert the links in the document to make them suitable for local
    viewing.  This affects not only the visible hyperlinks, but any part of the document that links to
    external content, such as embedded images, links to style sheets, hyperlinks to non-HTML content,
    etc.

           Each link will be changed in one of the two ways:

              The links to files that have been downloaded by Wget will be changed to refer to the file they
               point to as a relative link.

               Example: if the downloaded file /foo/doc.html links to /bar/img.gif, also downloaded, then the
               link in doc.html will be modified to point to ../bar/img.gif.  This kind of transformation works
               reliably for arbitrary combinations of directories.

              The links to files that have not been downloaded by Wget will be changed to include host name and
               absolute path of the location they point to.

               Example: if the downloaded file /foo/doc.html links to /bar/img.gif (or to ../bar/img.gif), then
               the link in doc.html will be modified to point to http://hostname/bar/img.gif.

           Because of this, local browsing works reliably: if a linked file was downloaded, the link will refer
           to its local name; if it was not downloaded, the link will refer to its full Internet address rather
           than presenting a broken link.  The fact that the former links are converted to relative links
           ensures that you can move the downloaded hierarchy to another directory.

           Note that only at the end of the download can Wget know which links have been downloaded.  Because of
           that, the work done by -k will be performed at the end of all the downloads.
source manpages: wget