A simple launcher     06/01/21
------------------------------------------------------------
I enjoy the ability to launch things simply. I want 
something like dmenu, but haven't found it yet. the bar 
program doesn't work for me... It compiles and runs, but 
won't launch anything, no matter what I do.

I settled for the solution below, which I called launch.c... 
if you've looked at the source for bar, you'll see I lifted 
their placement function (modified to only one placement).

Before I paste launch.c, let me tell you how I use it. I 
created $home/bin/rc/launcher, an rc script, which takes the 
output from launch and runs stuff with it. This means I can 
use any keyboard key (launch reports the keycode), to launch 
any program etc. awk takes the stdout and uses it to launch.
In practice, I have a square at the top-right where I can 
click, then hit a key to launch a few things.

Here's the rc script, followed by launch.c:

#!/bin/rc
# launcher script for use with launch
launch \
	| awk '
		/116/ {system("window -dx 600 -dy 400")}
		/102/ {system("fsterm")}
		/110/ {system("window -dx 1000 -dy 700 netsurf")}
		/97/  {system("window -dx 1000 -dy 600 acme")}
		'



/* begin launch.c */
#include <u.h>
#include <libc.h>
#include <draw.h>
#include <event.h>
#include <keyboard.h>

#define MAX(a,b) ((a)>=(b)?(a):(b))

enum {
	Off = 3,
};

static int wctl, width=100, height=100;

void
eresized(int new)
{
	if(new&& getwindow(display, Refnone) < 0)
		sysfatal("can't reattach to window");
}

static void
place(void)
{
	int w, h, minx, miny, maxx, maxy;
	char t[64];

	fprint(wctl, "top");

	w = Dx(display->image->r);
	h = Dy(display->image->r);

	miny = 0;
	maxy = height;
	minx = MAX(100, w-(Borderwidth+Off+width+Off+Borderwidth));
	maxx = w;

	snprint(t, sizeof(t), "resize -r %d %d %d %d", minx, miny, maxx, maxy);
	write(wctl, "current", 7);
	if(fprint(wctl, "%s", t) < 0)
		fprint(2, "%s: %r\n", t);
}


void
main(int argc, char* argv[])
{
	USED(argc, argv);

	Event ev;
	int e;
	initdraw(0,0, "Launch");
	eresized(0);
	einit(Ekeyboard);

	if((wctl = open("/dev/wctl", ORDWR)) < 0)
		sysfatal("%r");
	place();

	for(;;) {
		e = event(&ev);
		if(e == Ekeyboard) {
			print("%d\n", ev.kbdc);
			if(ev.kbdc == 27) {
				print("Escaped\n");
				break;
			}
		}
	}
}
/* end launch.c */