:sig
function posix_info(key : string, value : dval) dval

:params
key : `signal_name`
value : the value for `key`

:returns
The value for `key`.

:errors
The function stops with an error for an unknown key. The error lists the valid keys.

:content
`posix_info("signal_name", value)` returns the POSIX signal name for a signal number.

:example capy render
print(string(posix_info("signal_name", 11)), "\n")

:see-group
diagnostics
