Provided by: zsync_0.6.1-3ubuntu1_i386 bug

NAME

       zsync - Partial/differential file download client over HTTP

SYNTAX

       zsync  [  -u url ] [ -i inputfile ] [ -o outputfile ] [ { -s | -q } ] [
       -k file.zsync ] [ -A hostname=username:password ] { filename | url }

       zsync -V

DESCRIPTION

       Downloads a file over HTTP. zsync uses  a  control  file  to  determine
       whether any blocks in the file are already known to the downloader, and
       only downloads the new blocks.

       Either a filename or a URL can be given on the command line -  this  is
       the  path  of the control file for the download, which normally has the
       name of the actual file to downlaod with .zsync  appended.  (To  create
       this  .zsync  file  you have to have a copy of the target file, so this
       file should be generated by the person providing the download).

       zsync downloads to your current directory. It looks for any file in the
       directory of the same name as the file to download. If it finds one, it
       assumes that this is an earlier or incomplete version of the  new  file
       to  download,  and  scans  this  file for any blocks that it can use to
       build the target file. (It also looks for a file of the same name  with
       .part  appended,  so  it will automatically find previously interrupted
       zsync downloads and reuse the data already downloaded. If you know that
       the local file to use as input has a different name, you must use -i)

       zsync  retrieves  the  rest  of  the  target  file  over HTTP. Once the
       download is finished, the old version (if the new file wants  the  same
       name)   is   moved   aside  (a  .zs-old  extension  is  appended).  The
       modification time of the file is set to  be  the  same  as  the  remote
       source file (if specified in the .zsync).

OPTIONS

       -A hostname=username:password
              Specifies  a  username  and  password  to be used with the given
              hostname.  -A  can  be  used  multiple  times  (with   different
              hostnames), in cases where e.g. the
               .zsync  file  is  on  a  different server from the download, or
              there are multiple download servers (there  could  be  different
              auth  details  for  different  servers - and zsync never assumes
              that your password should be sent to a server other than the one
              named - otherwise redirects would be dangerous!).

       -i inputfile
              Specifies  (extra) input files. inputfile is scanned to identify
              blocks in common with the target file and zsync uses any  blocks
              found. Can be used multiple times.

       -k file.zsync
              Indicates  that  zsync  should  save  the  zsync  file  that  it
              downloads, with the given filename. If that file already exists,
              then  zsync  will  make a conditional request to the web server,
              such that it will only download it again if the server's copy is
              newer.  zsync  will  append .part to the filename for storing it
              while it is downloading, and will only overwrite the  main  file
              once  the download is done - and if the download is interrupted,
              it will resume using the data in the .part file.

       -o outputfile
              Override the default output file name.

       -q     Suppress the progress bar, download rate and ETA display.

       -s     Deprecated synonym for -q.

       -u url This specifies the referring URL.  If you  have  a  .zsync  file
              locally  (if  you  downloaded it separately, with wget, say) and
              the .zsync file contains a relative URL,  you  need  to  specify
              where  you  got  the  .zsync file from so that zsync knows which
              server and path to use for the rest of  the  download  (this  is
              analogous to adding a <base href="..."> to a downloaded web page
              to make the links work).

       -V     Prints the version of zsync.

FILES

ENVIRONMENT VARIABLES

       http_proxy
              Should be the [http://]hostname:port for your web proxy, if  one
              is required to access the target web server(s).

EXAMPLES

       zsync                                                                -i
       /var/lib/apt/lists/server.debian.org_debian_dists_etch_main_binary-
       i386_Packages http://zsync.moria.org.uk/s/etch/Packages.zsync

AUTHORS

       Colin Phipps <cph@moria.org.uk>

SEE ALSO

       zsyncmake(1)