pkg/53025: spamd(8) from mail/spamassassin cannot be stopped after reloading

[khorben%defora.org@localhost]

>Number:         53025
>Category:       pkg
>Synopsis:       spamd(8) from mail/spamassassin cannot be stopped after reloading
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Feb 13 23:50:00 +0000 2018
>Originator:     Pierre Pronchery
>Release:        pkgsrc-2017Q3
>Organization:
>Environment:
NetBSD host.name 8.0_BETA NetBSD 8.0_BETA (GENERIC) amd64
>Description:
The init script for spamd sends SIGHUP for reloading, after locating the PID in /var/run/spamd.pid, and this works fine the first time. However, then the Perl interpreter changes argv[0] to e.g. /usr/pkg/bin/perl5.26.0 and the init script will not be able to match the process anymore with the PID registered. spamd(8) then has to be stopped, restarted or otherwise interacted with manually.
>How-To-Repeat:
# ps auxw | grep 1234
root    1234  0.0 14.8 154984 77572 ?       Ss   12:37AM 0:01.24 /usr/pkg/bin/perl -T -w /usr/pkg/bin/spamd -u _spamd -i 127.0.0.1
# /etc/rc.d/spamd status
spamd is running as pid 1234.
# /etc/rc.d/spamd reload
Reloading spamd config files.
# /etc/rc.d/spamd status
spamd is not running.
# cat /var/run/spamd.pid                                                   
1234
# ps auxw | grep 1234
root    1234  0.0 14.8 154984 77572 ?       Ss   12:37AM 0:01.24 /usr/pkg/bin/perl5.26.0 -T -w /usr/pkg/bin/spamd -u _spamd -i 127

>Fix: