Is it possible to specify a temporary directory instead of /tmp?

[Frédéric]

Hi,
I'm trying to generate scores from a web page but my http server
(apache) is not allowed to write in /tmp (SELinux). I am allowed to
write in a specific directory where I save the .ly and .pdf but
lilypond generates the postscript file /tmp which fails when ran from
the web site.
Can I specify a specific temporary directory?
Regards,
F