delete downloaded marked emails after specific days & pop3 advice

[jindam, vani]

after much trials, i found its impossible to run
dovecot on debian 11 on userland (1). i have a
copy of gnus manual (by lars magne, 1995-2015,
no version). recently disvovered check paren
for looking errors on .gnus

i have few questions:

(a) is it possible to download all emails on my
local machine, i dont want to retain email copies
on server
(b) do i have to specify all email directories
on .gnus for downloading, ex: spam, draft
(c) how do i auto expunge all marked emails on
.gnus or mbsync.rc after specific period
(d) seriously, reconsidering to use getmail
to fetch all emails through pop3, is it good
idea. pop3 supports or recognises only one
directory —inbox & does it mean it will include
spam emails in inbox?

* mbsync.rc:
IMAPAccount disroot
Host disroot.org
User jindam.vani@disroot.org
SSLType IMAPS
SSLVersions TLSv1.2

# you may have to tweak the awk here + filename to your netrc/authinfo:
# PassCmd "gpg2 -q --for-your-eyes-only --no-tty -d $HOME/.netrc.gpg | 
awk '$2==\"mail.messagingengine.com\" && $4==\"me@fastmail.com\" {print 
$6;exit(0)}'"
# Port 992
# Port 992 has a "flat" hierarchy; use with
# mail_location = maildir:~/.Maildir/:LAYOUT=fs:INBOX=~/.Maildir/INBOX
# in dovecot (see also MaildirStore.Inbox below)

IMAPStore disroot-remote
Account disroot

MaildirStore disroot-local
# The trailing "/" is meaningful
Path ~/.Maildir/
Inbox ~/.Maildir/INBOX
SubFolders Legacy

Channel disroot
Master :disroot-remote:
Slave :disroot-local:
Patterns *
Create Slave
Sync All
Expunge Both
SyncState *

* .gnus:
(setq gnus-select-method '(nnnil ""))

(add-to-list 'gnus-secondary-select-methods
             '(nnmaildir ""
              (directory "/home/jin/.Maildir/")
              (get-new-mail t)
              (directory-files nnheader-directory-files-safe)))

(setq mail-user-agent 'gnus-user-agent)
(setq read-mail-command 'gnus)


(1) https://github.com/CypherpunkArmory/UserLAnd

regards,
jindam, vani

--
toots: @jindam_vani@c.im
others: en.wikipedia.org/wik//User:Jindam_vani