How to prevent a program from crashing when the "OSError: Too many open files" error occurs?

[mrhdias]

Strange because if I fix the filesize it doesn't crash! 
    
    
    # let filesize = cast[int](getFileSize(path))
    let filesize = 104
    
    let file = openAsync(path, fmRead)
    file.close()
    
    
    Run

So the problem has to do with the getFileSize function