$ curl cheat.sh/
# genisoimage
# Pre-mastering program to generate ISO9660/Joliet/HFS hybrid filesystems.
# More information: <https://manpages.debian.org/latest/genisoimage/genisoimage.1.en.html>.

# Create an ISO image from the given source directory:
genisoimage -o myimage.iso path/to/source_directory

# Create an ISO image with files larger than 2GiB by reporting a smaller apparent size for ISO9660 filesystems:
genisoimage -o -allow-limited-size myimage.iso path/to/source_directory

$
Follow @igor_chubin cheat.sh tldr