Dear all,
If you want to install the current idl 8.2 on Linux, you can of course get the latest tar file from the idl web site. For linux you can, alternatively, just get it from my web site (see below). Assuming that you have superuser access, and can just do the following. (This time, thinks are slightly different from last time, so my description is not quite precise and you may want to adjust the link yourself to make things work correctly.)

cd /usr/local/itt
sudo wget http://norlx51.albanova.se/~brandenb/downloads/idl85envi53sp1linux.x86_64.tar.gz
sudo wget http://norosx52.albanova.se/~brandenb/downloads/idl85envi53sp1linux.x86_64.tar.gz
sudo tar xopf idl85envi53sp1linux.x86_64.tar.gz
sudo wget http://lcd-www.colorado.edu/~axbr9098/downloads/idl85envi53sp1linux.x86_64.tar.gz
sudo wget http://norlx51.albanova.se/~brandenb/downloads/idl85envi53sp1linux.x86_64.tar.gz
#sudo wget http://norlx51.albanova.se/~brandenb/downloads/idl82linux.x86_64.tar.gz
#sudo wget http://norosx52.albanova.se/~brandenb/downloads/idl82linux.x86_64.tar.gz
sudo tar xopf idl85envi53sp1linux.x86_64.tar.gz
sudo tar xzvf idl85envi53sp1linux.x86_64.tar.gz
#sudo tar xopf idl82linux.x86_64.tar.gz
sudo ./install.sh

If you don't have superuser permissions, you could just make a local itt directory underneath your home directory, or somewhere. On a mac, you get instead

http://norlx51.albanova.se/~brandenb/downloads/InstallIDL81_Mac.pkg

Then it asks a few questions to which the answer is always "yes", except when it comes to the following (now second) question:

Do you want to start the DICOM Network Services at boot time?  Root permissions are required.? (y/n): n

So here you say no. If you miss it and say "yes", you just do the whole cycle again. For me it works without problems. For the installation directory, you can just enter a dot, if you mean the current working directory. Regarding the question about the License Wizard, I say "no" and copy the license.dat file into the license directory myself.
Axel

PS: on another machine where you don't have root access, go to a suitable directory, and say, e.g.,

cd /afs/pdc.kth.se/misc/tmp/projects/prj.2007-08.brandenb.1/itt
wget http://norlx51.albanova.se/~brandenb/downloads/idl81linux.x86.tar.gz
tar xopf idl81linux.x86.tar.gz
./install.sh

and proceed as before. In your .cshrc file, you'd need to set, e.g.,

  setenv IDL_DIR /afs/pdc.kth.se/misc/tmp/projects/prj.2007-08.brandenb.1/itt/idl/idl
  setenv IDL_PATH "../idl:+~/idl:+"$IDL_DIR
  alias idl $IDL_DIR/bin/idl

Axel Brandenburg
$Date: 2016/06/13 00:35:47 $, $Author: brandenb $, $Revision: 1.21 $