centos man page for systemd-ask-password

SYSTEMD-ASK-PASSWORD(1) 				       systemd-ask-password					   SYSTEMD-ASK-PASSWORD(1)

NAME
       systemd-ask-password - Query the user for a system password

SYNOPSIS
       systemd-ask-password [OPTIONS...] [MESSAGE]

DESCRIPTION
       systemd-ask-password may be used to query a system password or passphrase from the user, using a question message specified on the command
       line. When run from a TTY it will query a password on the TTY and print it to STDOUT. When run with no TTY or with --no-tty it will query
       the password system-wide and allow active users to respond via several agents. The latter is only available to privileged processes.

       The purpose of this tool is to query system-wide passwords -- that is passwords not attached to a specific user account. Examples include:
       unlocking encrypted hard disks when they are plugged in or at boot, entering an SSL certificate passphrase for web and VPN servers.

       Existing agents are: a boot-time password agent asking the user for passwords using Plymouth; a boot-time password agent querying the user
       directly on the console; an agent requesting password input via a wall(1) message; an agent suitable for running in a GNOME session; a
       command line agent which can be started temporarily to process queued password requests; a TTY agent that is temporarily spawned during
       systemctl(1) invocations.

       Additional password agents may be implemented according to the systemd Password Agent Specification[1].

       If a password is queried on a TTY, the user may press TAB to hide the asterisks normally shown for each character typed. Pressing Backspace
       as first key achieves the same effect.

OPTIONS
       The following options are understood:

       -h, --help
	   Prints a short help text and exits.

       --icon=
	   Specify an icon name alongside the password query, which may be used in all agents supporting graphical display. The icon name should
	   follow the XDG Icon Naming Specification[2].

       --timeout=
	   Specify the query timeout in seconds. Defaults to 90s. A timeout of 0 waits indefinitely.

       --no-tty
	   Never ask for password on current TTY even if one is available. Always use agent system.

       --accept-cached
	   If passed, accept cached passwords, i.e. passwords previously typed in.

       --multiple
	   When used in conjunction with --accept-cached accept multiple passwords. This will output one password per line.

EXIT STATUS
       On success, 0 is returned, a non-zero failure code otherwise.

SEE ALSO
       systemd(1), systemctl(1), plymouth(8), wall(1)

NOTES
	1. systemd Password Agent Specification
	   http://www.freedesktop.org/wiki/Software/systemd/PasswordAgents

	2. XDG Icon Naming Specification
	   http://standards.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html

systemd 208														   SYSTEMD-ASK-PASSWORD(1)