I have just spent a very frustrating evening trying to set the
LD_LIBRARY_PATH variable for RealPlayer 5.0. I tried initialising it in
/etc/profile but it never showed up in my environment and I couldn't
understand why not until I inspected the README for ld.so-1.9.9. It
seems that ld.so deletes this variable and all others like it whenever
it loads a setuid-root program. This must be a security issue, but then
why can't ld.so simply *ignore* LD_LIBRARY_PATH instead of deleting it,
and therefore give the program a change to drop its root privileges?
The root (no pun intended) of my problem here is that both xterm and su
are setuid-root programs.