FORTRAN 77 IO Error: Troubleshooting with FORCE 2.0

[Sujash Bhattacharya]

I have a FORTRAN code that is producing no error upon compilation but when I run it, the run aborts with following message

"open: illegal unit number
apparent state: unit 72 <unnamed>
last format: list io
lately writing direct formatted external IO

This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information"

I am using Force 2.0 as compiler. This code is running well in my professors pc with force 2.0. . The code is long. So it is difficult to post it here.

 

[DrClaude]

You'll have to post some code if you want anybody to help you. You can copy and paste the relevant part (including the open statement) inside code tags.

 

[jedishrfu]

Here's an online discussion about finding valid unit numbers:

http://computer-programming-forum.com/49-fortran/f569be913050064a.htm

I recall that 5 is for reading standard input and 6 is for writing to the printer ie standard output

and here's some related info from Intel on its fortran:

https://software.intel.com/en-us/forums/intel-fortran-compiler-for-linux-and-mac-os-x/topic/269404

where they note the shell may have issues with too many files open (another limit to consider).