[tex-live] Update all installed failed

[Philip Taylor (Webmaster, Ret'd)]

Zdenek Wagner wrote:

 > Just an idea: if you try to open tex.exe in the append mode and it
 > succeeds, you know that the file is not used and you can overwrite it.
 > you can immediatelly close it without writing anything. It may be good
 > to set the ctime to the old value. If opening fails, it means that the
 > file is in use. I do not know whether such an approach works but it
 > looks simple.

Well, it is certainly simple, and it is probably sufficient in 99.999%
of cases, but of course there is the theoretical possibility that
someone/thing might start to make use of tex.exe between the time that
you close it and the time you try to overwrite it.  I know next to
nothing about Windows programming, but in a more sophisticated
operating system such as VMS one would expect to have the ability
to take out an exclusive lock on the file which one would not
relinquish until the overwrite were complete.

** Phil.