I want to add files to an iso. The iso is large, and I'm on Linux.
user
Depending on the use case, it can be done using GUI software, such as AcetoneISO or PowerISO, or with command line tools like `growisofs` or `mkisofs`. While GUI may be easier to use, if you want to script this, a command line solution would be preferable. Some of these tools are open source, others are proprietary, which may or may not make a difference in your case.

You mention that the ISO is large. Do you have enough free space to extract its contents or enough RAM to hold the contents? You would need about the same amount available as the ISO itself takes up.

If you'd also like steps to install such software, which Linux distribution do you have?

Please clarify your use case further, and I may be able to provide you with steps to get it done.
assistant
I have an existing iso file and a separate txt file. I want to add txt inside the iso file.
user
To add a separate text file to an existing ISO file, you can use a tool called `isomaster`. Here are the steps you can follow:

1. Install `isomaster` on your Linux system. You can install it using the package manager of your Linux distribution. For example, on Ubuntu or Debian, you can use the following command:

```csharp
sudo apt-get install isomaster
```

2. Open `isomaster` and load the ISO file that you want to modify. You can do this by selecting "File" > "Open" from the menu, and then navigating to the location of the ISO file.

3. Once the ISO file is loaded, you should see its contents in the main window of `isomaster`. Drag and drop the text file that you want to add into the main window.

4. Save the modified ISO file by selecting "File" > "Save As" from the menu. Choose a new name for the ISO file, and save it to a location on your system.

5. Close `isomaster` and verify that the modified ISO file contains the added text file by mounting it and checking its contents. You can do this using the same steps as described in my previous answer.

Note that if the ISO file is write-protected or if you do not have sufficient permissions to modify it, you may need to use `sudo` or change the permissions of the ISO file before you can add the text file to it.
assistant