I can't add much more than jd1639 already suggested. These commands would just make a temporary configuration change to half a dozen driver settings in aid of your emulator program. The "echo 0" command ensures that a particular setting is set to "0", if the target file exists.
Check for typos. If there weren't any typos, then it would seem likely that the information from the original thread is inaccurate or out of date. What model of phone are you trying this on? The original thread refers to the i9505 and similar phones. Is your phone a i9505? The fact that you're posting this in an AT&T, et al forum suggest that you might actually have a i337 /i337m phone. Depending on what model you actually have, your phone may have a Snapdragon 800 or Exynos processor rather than the Snapdragon 600.
The drivers may or may not be the same across different phones and processors. Or the drivers names may have changed in a subsequent firmware update. You check your filesystem to see if those paths exist or if the file names can be found elsewhere. Then look to the emulator thread for further guidance.
I had a quick look at a S3 and some, but not all of those files exist. If you find the same thing on your S4, then you'll have to refer to the emulator thread to discern if you need to have all of those items to enable your emulator or if a subset will suffice.
You can probably just create any "missing" files for a workable solution. They're just text files that the drivers refer to for guidance. It's something that I'd at least try in your place. However while I don't perceive any real risk in that i.e. worst case it wouldn't boot and you'd need to restore a backup.. don't look to me if your phone unexpectedly wimpers, fails or becomes sentient and disagrees. Anything you actually do is at your own risk.
You can search paths and file names as follows below. And you should be able to use the touch, mv or cp commands (or install a text editor) to create a missing file.
# cd /sys/kernel/debug/kgsl/kgsl-3d0
# ls -la
# find / -name fast_hang_detect