.\" SPDX-License-Identifier: MIT
.
.Sh ENVIRONMENT VARIABLES
.Bl -tag -compact -width 4n
.It Ev TZPFMS_PASSPHRASE_HELPER
By default, passphrases are prompted for and read in on the standard output and input streams.
If
.Ev TZPFMS_PASSPHRASE_HELPER
is set and nonempty, it will be run via
.Pa /bin/ Ns Nm sh Fl c
to provide each passphrase, instead.
.Pp
The standard output stream of the helper is tied to an anonymous file and used in its entirety as the passphrase, except for a trailing new-line, if any.
The arguments are:
.Bl -tag -compact -offset 2n -width ".Li $1"
.It Li $1
Pre-formatted noun phrase with all the information below, for use as a prompt
.\" Passphrase for tarta-zoot
.\" New passphrase for tarta-zoot (again)
.It Li $2
Either the dataset name or the element of the TPM hierarchy being prompted for
.It Li $3
.Qq new
if this is for a new passphrase, otherwise blank
.It Li $4
.Qq again
if it's the second prompt for that passphrase, otherwise blank
.El
.Pp
If the helper doesn't exist
.Pq the shell exits with Sy 127 ,
a diagnostic is issued and the normal prompt is used as fall-back.
If it fails for any other reason, the prompting is aborted.
.
TZPFMS_PASSPHRASE_HELPER_MAN{}
.El