[tex-live] Installing TeX Live 2015 on shared host using jailshell

[Karl Berry]

    i found the script hard code about line 1216 /usr/local/textlive.

It is not hard-coded.  The operator on that line is ||=.

  $tex_prefix ||= '/usr/local/texlive';

Thus, as seen a half-dozen lines above, you can override that default
with the TEXLIVE_INSTALL_PREFIX environment variable.  (Also, everything
that depends on $tex_prefix should be separately definable, at least
that was the intent.)

Also, the string "/usr/local" does not appear in
http://pastebin.com/qTJ4umgi as far as my search can see, so I don't
understand.  I can't guess why the "untarring" of amstex failed.

Finally, you might look at .../2015/install-tl.log, if you haven't
already solved it.  (Seems like we should report that path when we say
"Installation failed".  It would also be nice if all the lines written
to the terminal went to the log.  Maybe one day.)

Good luck,
Karl