* Make sure to hide a password query dialog as soon as a) the `ask.xxxx` file is deleted, watch this with inotify. b) the `NotAfter=` time elapses, if it is set `!= 0`.
* Access to the socket is restricted to privileged users.
To acquire the necessary privileges to send the answer back, consider using PolicyKit.
- In fact, the GNOME agent we ship does that, and you may simply piggyback on that, by executing "`/usr/bin/pkexec /lib/systemd/systemd-reply-password 1 /path/to/socket`" or "`/usr/bin/pkexec /lib/systemd/systemd-reply-password 0 /path/to/socket`" and writing the password to its standard input.
+ In fact, the GNOME agent we ship does that, and you may simply piggyback on that, by executing "`/usr/bin/pkexec /usr/lib/systemd/systemd-reply-password 1 /path/to/socket`" or "`/usr/bin/pkexec /usr/lib/systemd/systemd-reply-password 0 /path/to/socket`" and writing the password to its standard input.
Use '`1`' as argument if a password was entered by the user, or '`0`' if the user canceled the request.
* If you do not want to use PK ensure to acquire the necessary privileges in some other way and send a single datagram
to the socket consisting of the password string either prefixed with "`+`" or with "`-`" depending on whether the password entry was successful or not.