[j-nsp] upgrade error

[Erol KAHRAMAN]

hi,
i have m7i box. Today i am trying to upgrade junos to 8.0 but i got the
following errror.

pkg_add: find_play_pen: can't find enough temporary space to extract the
files, please set your
PKG_TMPDIR environment variable to a location with at least 179231508 bytes
free
WARNING: Current configuration not compatible with /var/tmp/jinstall-
8.0R1.9-domestic-signed.tgz

how i can change my PKG_TMPDIR setting ?

-- 
Erol KAHRAMAN
System Network Administrator