Startup script of net/frr7 port contains unquoted call $(check_process ${command}) that may return a list, not single token only. In such case, the test [ -z $(check_process ${command}) ] emits syntax error similar to: [: 1176: unexpected operator It needs double quotes: [ -z "$(check_process ${command})" ] Normally, this error should not happen unless there is unrelated process in the system selected by check_process subroutine in addition to one of frr's.
A commit references this bug: Author: olivier Date: Mon Oct 5 07:48:18 UTC 2020 New revision: 551478 URL: https://svnweb.freebsd.org/changeset/ports/551478 Log: Harden RC script by adding double quotes. While here, document usage of frr_vtysh_boot. PR: 250099 Submitted by: eugen Changes: head/net/frr7/Makefile head/net/frr7/files/frr.in
Thanks Eugene!