IDL 8.8.x has a graphics issue on MacOS 12 Monterey, but here’s a work-around

[Ben C]

Apple released the newest iteration of MacOS, known as Monterey or MacOS 12, in October 2021. This version of MacOS is not officially supported by IDL 8.8.x and there are known issues, mainly:

• IDL graphics may fail to display, usually from Command Line IDL, giving the following error output: 

                  Error: Unresolved inheritance operation

For a complete break-down of officially supported platforms for ENVI and IDL, see THIS page. 

RECOMMENDED WORK-AROUND:  Change the IDL launch script to include an updated definition for DYLD_LIBRARY_PATH.  Administrator rights are required.

1. Open the file /Applications/harris/envi56/idl88/bin/idl in a text editor. On most Mac systems, you will need to do so with elevated permissions if installed in the default location. This is most easily done through Apple Terminal with…

     sudo vi /Applications/harris/idl88/bin/idl

2. Find the line that reads “export DYLD_LIBRARY_PATH” near the bottom of the file and change it to the following:

     export DYLD_LIBRARY_PATH=/opt/X11/lib/flat_namespace:$DYLD_LIBRARY_PATH

3.  Save the file and exit the text editor. IDL should now work normally.

NOTE: This work-around was tested with MacOS 12.0.1, ENVI+IDL 5.6.1, and XQuartz 2.8.1 on a system with an Intel CPU, but it is expected to work with IDL 8.8.0 and with Apple M1 chips as well.

 

ALTERNATIVE WORK-AROUND: Revert to an older version of IDL. IDL 8.7.3 appears to work out-of-the-box on Monterey.