:eval header argument can limit evaluation of specific code
blocks. It is useful for protection against evaluating untrusted ‘src’
code blocks by prompting for a confirmation. This protection is independent
never or no
Org will never evaluate this ‘src’ code block.
Org prompts the user for permission to evaluate this ‘src’ code block.
never-export or no-export
Org will not evaluate this ‘src’ code block when exporting, yet the user can evaluate this source block interactively.
Org prompts the user for permission to export this ‘src’ code block.
:eval header argument is not set for a source block, then Org
determines whether to evaluate from the
variable (see Code evaluation security).