Demand file from the author

1. extract idl85envi53sp1linux.x86_64.tar.gz
   do it for every new install
2. execute installation

-> sudo ./install.sh

to default directory

3. copy bin.linux.x86_64 to /usr/local/exelis/idl85/bin

-> sudo cp  -r [$IDL85]/bin.linux.x86_64 /usr/local/exelis/idl85/bin
-> chmod -r a+x  /usr/local/exelis/idl85/bin.linux.x86_64

rename original one for backup reason

5. Put the following line in to .bashrc
   source /usr/local/exelis/idl85/bin/idl_setup.bash
   or idl_setup (csh)
   SSW:
   define a tcsh shell script: ssw_start.csh

#!/bin/tcsh -f 
setenv SSW /usr/local/ssw
setenv SSW_INSTR "aia hmi sot"
setenv IDL_STARTUP dir-to-start/startup.pro
# The following line could replace .bashrc line for IDL if IDL is only used in SSW
# sh /usr/local/exelis/idl85/bin/idl_setup.bash 
source $SSW/gen/setup/setup.ssw
source $SSW/gen/setup/setup.ssw
source $SSW/gen/setup/setup.ssw_alias
source $SSW/site/setup/setup.ssw_paths
source $SSW/site/setup/setup.ssw_env
sswidl

define ssw_startup.pro:

DEVICE, RETAIN = 2
DEVICE,DECOMPOSED=0
!PATH = !PATH + ':' + EXPAND_PATH('+idl')   

put ssw_start.csh and ssw_startup.pro in a directory
e.g. ~/bin/
add a line into .bashrc:
alias ssw='csh ~/bin/ssw_start.csh'
source .bashrc
. .bashrc

SSW upgrade