Changing temp directory on Ubuntu

I had small disk space on my PC. Therefore, I added a new SATA hard drive to allocate more disk space to Matlab. The new hard drive is mounted on a dircetory called /hdd2TB/. I also changed the value of environment variable 'TMP' both in the /etc/environment file and using setenv() function. Now tempdir command returns:

'/hdd2TB/'

or in terminal:

echo $TMP
/hdd2TB/

Yet, /tmp/ directory grows in size when I run my simulations and /hdd2TB/ does not change.

Answer 1

[Seyed Ali Baradaran Birjandi]

I found a workaround for the problem by making tmp directory a symbolic link to my new hard drive.