bug#57283: opensmtpd: permission issue while trying to deliver messages to mboxes in /var/mail

[semente]

Hello,

After setup opensmtpd service in a Guix system I could use it to send local 
messages but the messages won't be delivered to user's default mailboxes due 
lack of write permissions for the /var/mail directory.

I could only fix this by changing /var/mail permissions to 777. I also tried 
changing its owner to the user that runs opensmtpd (smtpd user) but it worked 
only when I give write permissions to all.

Related error logs:

  Aug 18 14:48:32 localhost lockspool: /var/mail/semente.lock: Permission denied
  Aug 18 17:50:39 localhost smtpd[12620]: 55190016986121ba mda delivery 
evpid=f923e987d2d9e39b from=<semente@host> to=<semente@host> 
rcpt=<semente@host> user=semente delay=25m10s result=TempFail stat=Error 
(terminated; timeout)

Thanks,
semente