VERIFIED SOLUTION i

Resolve error/warning installing AcuCobol runtime, MailStream Plus, or CODE-1 Plus on UNIX/Linux, install could not uncompress tar file (or other tar file). Due to lack of space available on drive.

Operating System: UNIX/Linux
All versions of MSP (problem found during  8.3.2 install), CODE-1 Plus, Acucobol, possibly others

Issue

While trying to do an install on UNIX AIX, the install script ended with an error:
--------------------------
A problem was encountered while extracting (tar) the runtime system 
(aix7.1x_32) into /usr/g1/test/msn/rts. 
--------------------------


(Although it could have happened with another tar file too.)

Cause

The message also gives a suggestions to try: 
acushare -kill
and then 
slibclean (as root)

But in this case, that did not solve issue.  
A Pitney Bowes UNIX/Linux Specialist was brought in to work with the customer on a conference call/screen share.  After trying numerous things with no success, he had the customer try to manually uncompress the tar file as a test, and got an error saying that there was not enough space.

He then checked the drive space for the area the install was going into, and found that it was 100% full. 

The Specialist found this odd, because the UNIX/Linux install scripts know how much space is needed for the complete install, and checks for that amount before proceeding with the install.  If there is not enough, the install script normally gives a specific error that there is not enough space to install whatever it's installing. 
 

Resolution

UPDATED: September 1, 2017
Once the user deleted some things to make more space available, the install completed normally.