Fuego provides a feature to grab a "snapshot" of board status information
and save that along with other data associated with the run. The idea
is that this status information might be helpful for diagnosing the issue
when a problem is encountered during a test (either test failure or an
error during test execution).

This status information is obtained during the 'snapshot' phase of test
execution.  The 'snapshot' phase of execution is turned on by default,
but if the phases are manually enumerated, this phase can be omitted.

The letter 's' is used to specify the 'snapshot' phase of test execution,
with the '-p' option in 'ftc run-test'.

The default snapshot operation calls [[function_ov_rootfs_state|ov_rootfs_state]].

The board status data is saved in the file: ``machine_snapshot.txt``
in the log directory for a run (that is, under /fuego-rw/logs).

= Overriding snapshot operations =
There are two ways to override the snapshot operation, one on a per-board
basis and one on a per-test basis.

To override the operation on a per-board basis,
the function ov_rootfs_state can can be overridden.
This is done by creating a custom distribution overlay file,
and then using the DISTRIB variable in the board file for a board.

To override the operation on a per-test basis, a test can
define its own 'test_snapshot' function.  If defined, then this function
will be called in place of the default snapshot function in the
Fuego core.

See [[function_test_snapshot|test_snapshot]] for information about how
to define this function in a fuego_test.sh script.