[syslinux] "--once" support / ADV

[Garth Hitchens]

I wonder if anyone can help me understand syslinux —once support - it appears supported since 4.00 (it's in the changlog), but the syslinux (4.07) command gives the message "At least one specified option not yet implemented for this installer.".   anyone using boot-once with syslinux?

Alternate question:  since this is for an embedded device I would prefer not to have to install the syslinux installer on the device -- is there an alternate way to write directly to the ADV (like a known offset into a file or partition or boot record) that would allow me to enable boot-once?  I like syslinux but I'm trying to get firmware upgrades working on an embedded device and need boot-once functionality.  Am I out of luck?