Looking in g_canvas.c, canvas can take a "click" message followed by 5 floats. The arguments are "t_floatarg xpos, t_floatarg ypos, t_floatarg shift, t_floatarg ctrl, t_floatarg alt" but it none of those are used, at least by the following function:

static void canvas_click(t_canvas *x,
    t_floatarg xpos, t_floatarg ypos,
        t_floatarg shift, t_floatarg ctrl, t_floatarg alt)
{
    canvas_vis(x, 1);
}

It seems to only make the canvas visible, so try sending "click 0 0 0 0 0" to a named canvas...

On Jul 28, 2017, at 6:32 PM, pd-list-request@lists.iem.at wrote:

From: Roman Haefeli <reduzent@gmail.com>
Subject: [PD] how to emulate mouse left-click to canvas?
Date: July 28, 2017 at 4:55:26 PM GMT+2
To: Pd-List <pd-list@lists.iem.at>


Hey all

Is it still possible in Pd to send a message to canvas in order to
emulate a mouse click? Some documents[1] and patches[2] on the Pure
Data wiki suggest it was possible with earlier versions of Pd, but I
can't get the examples to work with current Pd. 

My aim is to make a symbolatom ready for text input without clicking it
first. 

Roman

--------
Dan Wilcox
@danomatika
danomatika.com
robotcowboy.com