@verb #9359:"set_message_unread" this none this rxdo #8084
@program #9359:"set_message_unread" this none this
{message_id, who, ng} = args
caller_perms():controls(who) || raise(E_PERM)
mid = this:message_id(message_id, ng)
propname = " " + tostr(toint(who))
unread = `this.(propname) ! E_PROPNF'
if (unread == E_PROPNF)
  add_property(this, propname, {{ng, mid}}, {$postman, ""})
else
  i = listiassoc(ng, unread)
  if (!i)
    unread = {@unread, {ng, mid}}
  else
    unread[i] = setadd(unread[i], mid)
  endif
  this.(propname) = unread
endif
"Last modified by Dax (#789) on Tue May  3 14:12:00 2005 MDT."
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