Команда: join
join files splitted by sfk split

with sfk join for Windows, Mac OS X, Linux and Raspberry Pi.
sfk join inputfile.part1 [outputfilebase] [-test]

join many input files into one output file. input files
must have extensions like .part1, .part001 etc.

if outputfilebase is omitted, outputfilename is just
like inputfile, but without the ".part1" extension.

options
   -test   does not really join the files, but reads all
           input files, telling the overall md5 checksum.
           join -test is recommended after every "sfk split"
           command, to verify if the splitted files are ok
           and can be rejoined.
   -force  if the output file exists already, overwrite it
           without asking back.

see also
   sfk split   split large files into smaller ones
   sfk media   join files of any name by using sfk
               select -sort ... +media -joinraw
               without checksum verification.
   sfk snapto  join text files into one document

web reference
   http://stahlworks.com/sfk-join

examples
   sfk join d:\transfer\easy.avi.part1 e:\full.avi
      joins easy.avi.part1, .part2 etc. into full.avi

   sfk join -test d:\transfer\easy.avi.part1
      simulates joining (does not write any output file),
      and tells if the input files are ok, by checksum.
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