Re: [PATCHv2 04/10] gdb/gdbserver: add new qDefaultExecAndArgs packet

[Eli Zaretskii <eliz@gnu.org>]

> From: Andrew Burgess <aburgess@redhat.com>
> Cc: Andrew Burgess <aburgess@redhat.com>,
> 	Eli Zaretskii <eliz@gnu.org>
> Date: Fri, 25 Aug 2023 16:34:37 +0100
> 
> diff --git a/gdb/NEWS b/gdb/NEWS
> index c4b1f7a7e3b..d78929c1398 100644
> --- a/gdb/NEWS
> +++ b/gdb/NEWS
> @@ -105,6 +105,14 @@
>    'inferior' keyword with either the 'thread' or 'task' keywords when
>    creating a breakpoint.
>  
> +* When connecting to a remote server, if the server supports the
> +  qDefaultExecAndArgs packet, then GDB will copy the argument string
> +  from the server and update the 'args' setting, as if 'set args ...'
> +  had been used.  This means that the arguments are visible from GDB
> +  using 'show args', and that, if using the extended-remote protocol,
> +  subsequent runs of the inferior will use the same arguments as the
> +  first run.
> +
>  * New commands
>  
>  set debug breakpoint on|off
> @@ -278,6 +286,13 @@ info main
>       inferior specific, then this field contains None.  This field can
>       be written too.
>  
> +* New remote packets
> +
> +qDefaultExecAndArgs
> +  This packet returns the executable filename and argument string with
> +  which the server was started.  If no such information was given to
> +  the server then this is reflected in the reply.
> +
>  *** Changes in GDB 13
>  

This part is OK.

> +@item S;@var{PP@dots{}};@var{AA@dots{}}
> +The program filename provided to the remote server when it started was
> +@var{PP@dots{}}, which is a hex encoded string, and the argument
> +string passed to the program when started by the server was
> +@var{AA@dots{}}, which is also a hex encoded string.

Here, PP and AA don't stand for literal "PP" and "AA" strings, they
stand for 2 or more hex-encoded characters, right?  In that case, PP
and AA should be in lower-case.  Moreover, I question the need to use
such cryptic names; why not say something like this instead:

  @item S;@var{prog};@var{args}
  The program filename provided to the remote server when it started was
  @var{prog}, which is a hex encoded string of zero or more characters,
  and the argument string passed to the program when started by the
  server was @var{args}, which is also a hex encoded string.

IOW, what is the significance of using two characters in PP and AA?

Reviewed-By: Eli Zaretskii <eliz@gnu.org>