doc: add disable saving roundup-admin history file for password changes

Author: rouilj

doc/admin_guide.txt

@@ -2151,13 +2151,16 @@ you can put the initialise command and password on the command
 line. But this allows others on the host to see the password (using
 the ps command). To initialise a tracker non-interactively without
 exposing the password, create a file (e.g init_tracker) set to mode
-600 (so only the owner can read it) with the contents:
+600 (so only the owner can read it) with the contents::
 
    initialise admin_password
 
-and feed it to roundup-admin on standard input. E.G.
+and feed it to roundup-admin on standard input. E.G.::
 
-  cat init_tracker | roundup-admin -i tracker_dir
+  cat init_tracker | roundup-admin -i tracker_dir -P history_features=2
+
+setting the pragma ``history_features=2`` prevents storing the command
+in the user's history file.
 
 (for more details see https://issues.roundup-tracker.org/issue2550789.)
 

doc/upgrading.txt

@@ -2188,7 +2188,7 @@ running::
     roundup-admin -i <tracker_home> table password,id,username
 
 Look for lines starting with ``{CRYPT}``. You can reset the user's
-password using::
+password using [#history-pragma]_ ::
 
     roundup-admin -i <tracker_home>
     roundup> set user16 password=somenewpassword
@@ -2199,6 +2199,14 @@ prompt). This prevents the new password from showing up in the output
 of ps or shell history. The new password will be encrypted using the
 default encryption method (usually pbkdf2).
 
+.. [#history-pragma] If your version of roundup-admin provides history
+  support, you should add ``-P history_features=2`` to the command
+  line or run ``pragma history_features=2`` at the ``roundup>``
+  prompt. This will prevent the command line (and password) from being
+  saved to your history file (usually ``.roundup_admin_history`` in
+  your user's home directory.  You can use ``roundup-admin -i
+  <tracker_home> pragma list`` to see if pragmas are supported.
+
 Enable performance improvement for wsgi mode (optional)
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