setup.sh hardcodes /tmp, should honor $TMPDIR

[martinpitt]

Hello,

in our environment (Ubuntu Snappy), packaged apps cannot currently access /tmp/, but the environment sets $TMPDIR (and $TEMPDIR) to an appropriate place, see https://en.wikipedia.org/wiki/TMPDIR. But catkin's setup.sh.in doesn't honor that, but does

 _SETUP_TMP=`mktemp /tmp/setup.sh.XXXXXXXXXX`

It should call mktemp --tmpdir setup.sh.XXXXXXXXXX instead to honor those.

This is at https://github.com/ros/catkin/blob/indigo-devel/cmake/templates/setup.sh.in#L47 at the time of this writing.

[wjwwood]

@martinpitt Thanks for the bug report, but I think we aren't currently using that because that isn't an option on all systems with mkdir, for example on OS X:

% mktemp --tmpdir setup.sh.XXXXXXXXXX
mktemp: illegal option -- -
usage: mktemp [-d] [-q] [-t prefix] [-u] template ...
       mktemp [-d] [-q] [-u] -t prefix

However, TMPDIR is set:

% export | grep TMPDIR
TMPDIR=/var/folders/40/ldgcl5kd1msgg5p_hcxbthzr0000gn/T/

Perhaps something else might be more cross-platform compatible.