136   if tarfile =~# '\.\(gz\|tgz\)$'
        137 "   call Decho("1: exe silent r! gzip -d -c ".s:Escape(tarfile)." | ".g:tar_cmd." -".g:tar_browseoptions." - ")
       *138    exe "silent r! gzip -d -c -- ".s:Escape(tarfile)." | ".g:tar_cmd." -".g:tar_browseoptions." - "
        139   elseif tarfile =~# '\.lrp'
        140 "   call Decho("2: exe silent r! cat -- ".s:Escape(tarfile)."|gzip -d -c -|".g:tar_cmd." -".g:tar_browseoptions." - ")
       *141    exe "silent r! cat -- ".s:Escape(tarfile)."|gzip -d -c -|".g:tar_cmd." -".g:tar_browseoptions." - "
        142   elseif tarfile =~# '\.bz2$'
        143 "   call Decho("3: exe silent r! bzip2 -d -c ".s:Escape(tarfile)." | ".g:tar_cmd." -".g:tar_browseoptions." - ")
       *144    exe "silent r! bzip2 -d -c -- ".s:Escape(tarfile)." | ".g:tar_cmd." -".g:tar_browseoptions." - "
        145   else
        146 "   call Decho("4: exe silent r! ".g:tar_cmd." -".g:tar_browseoptions." ".s:Escape(tarfile))
      **147    exe "silent r! ".g:tar_cmd." -".g:tar_browseoptions." ".s:Escape(tarfile)
	[...]
        444 fun s:Escape(name)
        445   " shellescape() was added by patch 7.0.111
        446   if exists("*shellescape")
        447    let qnameq= shellescape(a:name)
        448   else
        449    let qnameq= g:tar_shq . a:name . g:tar_shq
        450   endif
        451   return qnameq
        452 endfun

 (*) s:Escape() does not suffice, as it fails to escape ``%'' and friends.

(**) tar(1) allows arbitrary command execution via options ``--to-command'',
     and ``--use-compress-program''.