[tex-live] tlpmgui on vista

[Philip Taylor (Webmaster)]

Let me start by saying that I have a lot of sympathy
for Wang's position; by default, Win/XP will set
the user environment variables TEMP and TMP to

	C:\DOCUME~1\<Username>\LOCALS~1\Temp

and if <Username> contains "funny" characters which
cause problems for the TeX Live GUI Installer, then
this is (in my opinion) a serious problem.

Suggesting that a user clobber his/her environment variables
to work around this is, IMHO, not a satisfactory solution.

The obvious solution (it seems to me) is to programatically
ascertain whether the installer can write to %TEMP% and/or
%TMP%, and -- if not -- to internally create a scratch
directory into which the installer /can/ write : given
the probability of two people attempting a concurrent
install under Vista to be numerically indistinguishable from
zero, it would not seem that the algorithm for deriving
the name for the scratch directory to be excessively complex.

My dwa zloty / er yuan's worth :-)

** Phil.