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isolyzer ISO file analyzer

February 14, 2020 — BarryK

The EasyDD utility was created to make it easy to write image files to USB-sticks. It is both a GUI and CLI -- in the former case, it can be found in the "Setup" menu, and in the latter case run "easydd" in a terminal to display help info.

In the case of compressed images, such as *.img.gz, easydd does an "integrity check" to make sure that the file is not corrupted. Not as good as an actual checksum hash, but still of value.

I want to add writing of hybrid-ISO files to USB-sticks. However, there is nothing in the ISO specification for performing an integrity check. A common problem is an ISO file not completely downloading, so the file is smaller than it should be -- but there is nothing in the format of the ISO that will recognize its tail is missing.

However, there is a python utility, isolyzer, that does a pretty good job of ascertaining what the size of the ISO should be. I can use this as the integrity checker in easydd.

Here is the project page:

I have created a PET (12.4KB):

This will work in Easy 2.2.10 (and earlier). All dependencies are there, except for 'python-six' -- which actually is in the devx SFS, so you will have to run the PPM (petget) and install it. Then to run it:

# isolyzer <name of iso file> will report all kinds of information, including the expected size, and the actual size. 

Tags: easy