Re: [PATCH] gdb: Allow GDB to _not_ load a previous command history

[Eli Zaretskii <eliz@gnu.org>]

> From: Andrew Burgess <andrew.burgess@embecosm.com>
> Cc: Andrew Burgess <andrew.burgess@embecosm.com>
> Date: Fri, 24 Jan 2020 21:29:00 +0000
> 
> I've updated the manual, and added some tests.
> 
> gdb/ChangeLog:
> 
> 	* top.c (write_history_p): Add comment.
> 	(show_write_history_p): Add header comment, give a different
> 	message when history writing is on, but the history filename is
> 	empty.
> 	(history_filename): Add comment.
> 	(history_filename_empty): New function.
> 	(show_history_filename): Add header comment, give a different
> 	message when the filename is empty.
> 	(init_history): Compare history_filename against nullptr, and only
> 	read history if the filename is not empty.
> 	(set_history_filename): Add header comment, and only make
> 	non-empty filenames absolute.
> 	(init_main): Make the filename argument to 'set history filename'
> 	optional.
> 
> gdb/doc/ChangeLog:
> 
> 	* gdb.texinfo (Command History): Extend description for
> 	GDBHISTFILE and GDBHISTSIZE, add detail about the filename for
> 	'set history filename' being optional.
> 
> gdb/testsuite/ChangeLog:
> 
> 	* gdb.base/default.exp: Remove test of 'set history filename'.
> 	* gdb.base/gdbinit-history.exp: Add tests for setting the history
> 	filename to the empty string.
> 	* lib/gdb.exp (gdb_init): Unset environment variables GDBHISTFILE
> 	and GDBHISTSIZE.

Thanks.  This should also be announced in NEWS.

>  @cindex save command history
>  @kindex set history save
>  @item set history save
>  @itemx set history save on
>  Record command history in a file, whose name may be specified with the
> -@code{set history filename} command.  By default, this option is disabled.
> +@code{set history filename} command.  By default, this option is
> +disabled.  The command history will be recorded when @value{GDBN}
> +exits.
>  
>  @item set history save off
> -Stop recording command history in a file.
> +Don't record the command history into the file specified by @code{set
> +history filename} when @value{GDBN} exits.

This should say that if the history file name is an empty string, that
disables saving the history, even if saving it is set on.