Re: [PATCH] dynamic printf

[Stan Shebs <stanshebs@earthlink.net>]

On 2/29/12 1:14 AM, Andreas Schwab wrote:
> Stan Shebs<stanshebs@earthlink.net>  writes:
>
>> This patch implements a "dynamic printf", which is basically a breakpoint
>> with a printf;continue as its command list - but with additional features
>> that make it more interesting.
> How about:
>
> break [LOCATION] [thread THREADNUM] [if CONDITION] [printf FORMAT,ARGS...]
>
> Andreas.
>

I've been wondering whether that might be a better idea.  An advantage 
of "dprintf" for the command line is that it can abbreviate to just "dp" 
and tab completion works, while the optional arguments to the break 
command don't have any way to abbreviate (although they probably 
could).  That's not super-compelling, as by its nature a printf command 
entails typing in format string, double quotes and newlines and all, and 
in practice I expect a lot of these will tend to accumulate in script files.

Another consideration is how the collection looks in an info break 
command.  If dynamic prints are a different kind of breakpoint, then you 
can (in theory) filter the breakpoint listing to a single category, but 
if they are just breakpoints with special commands, they'll continue to 
be in the big list.

My intuition isn't giving me a strong read on which approach users will 
like better.  As the goal is at least partly to entice 
printf()+recompile users into using a GDB command instead, I think it 
needs to be among GDB's simpler commands.  Maybe include both syntaxes, 
mapping down to same functionality?

Stan