fc -ap -R stalls when called from sched

[Sebastian Gniazdowski <sgniazdowski@xxxxxxxxx>]

Hello,
I call function __convey_on_period_passed() from sched +1 mechanism.
There, I read an IO file (file used for data conveying). I use the
neat trick that worked for me in past, but not now:

    # Read input using history mechanism
    local -a commands
    () { fc -ap -R "$datafile"; commands=( ${history[@]} ) }

Shell stalls for ~10 seconds, then continues with data correctly read.
Whole source with debug marks is here:

https://github.com/psprint/zconvey/blob/001a5378177dcfdd0de388e19f5c7ca067c0a89c/zconvey.plugin.zsh#L174-L183

Asciinema showing the effect:

https://asciinema.org/a/9mfxg2j1jcwvoo7tb5x6bagr4

Removing anonymous function doesn't help. Doing normal load via
commands=( "${(@f)"$(<$datafile)"}" ) does help.


The plugin is for: a) assigning IDs and names to Zsh sessions b) doing
"zconvey -n Devel vim ~/.zshrc" to fire up command on Zsh session
named "Devel" (not implemented yet, thus a manual print -rl -- is used
to fill IO file).

Best regards,
Sebastian Gniazdowski