[tex-live] Error using tlmgr

[Philip Taylor (RHUoL)]

Zdeněk Wagner wrote:
> This should be a question for Linux maintainers. All Linux 
> distributions provide its xzdec. CentOS and Fedora install it as 
> default, Raspbian requires manual installation of the .deb package, it 
> is probably the same in Debian. IMHO it is not a wise idea to 
> duplicate a part of a system distribution just because a user has not 
> installed it. And tlmgr cannot install it automatically because the 
> name of the package is distro dependent and the name of the packager 
> differs as well (dnf, yum, apt-get, ...). In addition, TeX Live (from 
> TUG, not from the packaging systems) should preferably be installed by 
> an ordinary user while the package containing xzdec must be installed 
> by root or using sudo.
Well, I am confused, Zdeněk.  What are all these instances of "xzdec" 
which accompanied the pre-test ?

** Phil.
--------
Directory of D:\TeX\Live\2017\tlpretest\tlpkg\installer\xz

17/04/2017  23:32            72,784 xzdec.amd64-freebsd
15/04/2017  13:58            73,008 xzdec.amd64-netbsd
26/04/2017  16:42            62,012 xzdec.armel-linux
25/11/2016  18:34            64,444 xzdec.armhf-linux
13/04/2017  21:24           111,104 xzdec.exe
15/04/2017  20:32            83,470 xzdec.i386-cygwin.exe
16/04/2017  22:49           100,536 xzdec.i386-darwin
17/04/2017  23:32            69,884 xzdec.i386-freebsd
13/04/2017  20:40            71,064 xzdec.i386-linux
15/04/2017  13:58            75,968 xzdec.i386-netbsd
19/04/2017  15:29            71,260 xzdec.i386-solaris
16/04/2017  22:49           127,900 xzdec.powerpc-darwin
29/04/2017  21:57            69,732 xzdec.powerpc-linux
19/04/2017  15:29            74,188 xzdec.sparc-solaris
15/04/2017  20:32            74,752 xzdec.x86_64-cygwin.exe
15/04/2017  23:15            76,276 xzdec.x86_64-darwin
16/04/2017  22:49            80,128 xzdec.x86_64-darwinlegacy
15/04/2017  01:00            72,472 xzdec.x86_64-linux
19/04/2017  15:29            76,568 xzdec.x86_64-solaris