Question: What is the max file size that SAS software can successfully read.
(without considering hardware limit)

Thanks in advance.

Answer: 
"The maximum size of a SAS data set in a Direct Access Bound Library is limited by the maximum size of the library, which is about 2986 GB on 3390 volumes."

<http://support.sas.com/kb/8/213.html>
Depends on HOW you read the file. If loading a hash table for instance, you are limited by memory.. If you are reading via a set or infile statement, with no or limited size output dataset, you are limited by the 'uptime' of your process - eg if / when you are forcibly logged off, or become disconnected from whatever you are reading.

Also, some datasets (eg with a large number of columns) may be impossible to read, as cannot load all the variables into the PDV due to memory limits. Again, this is an OS limitation and not SAS.