xscsize \- return size of an X display to a shell script
.SH SYNOPSIS
.B xscsize
-.RB [ \-bcx ]
+.RB [ \-bcmx ]
.RB [ \-d
.IR display ]
.SH DESCRIPTION
.B XHEIGHT
variables.
.PP
+With the
+.B \-m
+option (see below),
+.B xscsize
+instead reports the geometry of the individual monitors (CRTCs) of a
+(possibly) multihead display.
+.PP
Command line options can be used to force output in either Bourne or C
shell syntax. In the absence of any explicit instructions,
.B xscsize
Output the assignments in C shell syntax (usable by C and Terminal C
shells).
.TP 5
+.B \-m, \-\-multiscreen
+Output geometry information about the individual monitors of a
+(possibly) multihead display, rather than the overall size of the root
+window. This sets
+.B XNSCR
+to the number of monitors, and
+.BI XSCR n _X \fR,
+.BI XSCR n _Y \fR,
+.BI XSCR n _WIDTH \fR,
+and
+.BI XSCR n _HEIGHT \fR
+to the
+.IR x -
+and
+.IR y -coordinates
+of the pixel shown in the top-left of monitor
+.I n
+(starting from zero), and the width and height of monitor
+.I n
+in pixels. The monitors will be sorted in order of increasing
+.IR y -coordinate
+(i.e., top to bottom), with monitors with equal
+.IR y -coordinates
+sorted in order of increasing
+.IR x -coordinate
+(i.e., left to right). Usually, then, the first monitor will be at
+(0, 0).
+.IP
+This requires that support libraries for the X RANDR extension were
+available when
+.B xscsize
+was compiled, and that the display actually implements at least version
+1.2 of the RANDR extension. If not,
+.B xscsize
+will still accept the
+.B \-m
+option, and produce appropriately formatted output, but will assume that
+there is exactly one monitor, and that it shows the entire root window.
+.TP 5
.B \-x, --export
Output a variable export command, so that the screen size is inherited
by child processes. The default is to just set local shell variables.
.SH ENVIRONMENT
.TP
.B XWIDTH
-Set to the width of the display in pixels.
+Set to the width of the display in pixels (not in
+.B \-m
+mode).
.TP
.B XHEIGHT
-Set to the height of the display in pixels.
+Set to the height of the display in pixels (not in
+.B \-m
+mode).
+.TP
+.B XNSCR
+The number of monitors attached to the display (only in
+.B \-m
+mode).
+.TP
+.BI XSCR n _X
+The
+.I x -coordinate
+of the top-left pixel shown on monitor number
+.I n
+counting from zero (only in
+.B \-m
+mode).
+.TP
+.BI XSCR n _Y
+The
+.I y -coordinate
+of the top-left pixel shown on monitor number
+.I n
+counting from zero (only in
+.B \-m
+mode).
+.TP
+.BI XSCR n _WIDTH
+The width, in pixels, of the portion of the root window shown on monitor
+number
+.I n
+counting from zero (only in
+.B \-m
+mode).
+.TP
+.BI XSCR n _HEIGHT
+The height, in pixels, of the portion of the root window shown on monitor
+number
+.I n
+counting from zero (only in
+.B \-m
+mode).
.TP
.B SHELL
Used to decide the nature of the calling shell. If absent, a Bourne
#include <string.h>
#include <X11/Xlib.h>
+#ifdef HAVE_XRANDR
+# include <X11/extensions/Xrandr.h>
+#endif
+#include <mLib/alloc.h>
+#include <mLib/dstr.h>
#include <mLib/mdwopt.h>
#include <mLib/quis.h>
+/*----- Data structures ---------------------------------------------------*/
+
+struct screen {
+ int x, y;
+ unsigned wd, ht;
+};
+
/*----- Static variables --------------------------------------------------*/
static unsigned int flags = 0;
fp);
}
-static void print_var(const char *name, unsigned long value)
+static void print_var(const char *name, int index, unsigned long value)
{
+ dstr d = DSTR_INIT;
+
if (index >= 0) {
dstr_putf(&d, "XSCR%d_%s", index, name);
name = d.buf;
dstr_destroy(&d);
}
+static int compare_screen(const void *a, const void *b)
+{
+ const struct screen *s = a, *t = b;
+ if (s->y != t->y) return (s->y < t->y ? -1 : +1);
+ else if (s->x != t->x) return (s->x < t->x ? -1 : +1);
+ else return (0);
+}
+
int main(int argc, char *argv[])
{
Display *dpy;
unsigned f = 0;
unsigned long wd, ht;
int sc;
+#ifdef HAVE_XRANDR
+ Window root;
+ int rrev, rrerr, rrmaj, rrmin;
+ XRRScreenResources *res;
+ XRRCrtcInfo *crtc;
+ struct screen *scr;
+ size_t nscr, j;
+ int i;
+#endif
#define f_bogus 1u
+#define f_multi 2u
/* --- Parse command line options --- */
{ "display", OPTF_ARGREQ, 0, 'd' },
{ "bourne-shell", 0, 0, 'b' },
{ "c-shell", 0, 0, 'c' },
+ { "multiscreen", 0, 0, 'm' },
{ "export", 0, 0, 'x' },
{ 0, 0, 0, 0 }
};
- int i = getopt_long(argc, argv, "huv" "d:bcx", opt, 0);
+ int i = getopt_long(argc, argv, "huv" "d:bcmx", opt, 0);
if (i < 0) break;
switch (i) {
case 'h': help(stdout); exit(0); break;
case 'd': display = optarg; break;
case 'b': flags |= F_SH; break;
case 'c': flags |= F_CSH; break;
+ case 'm': f |= f_multi; break;
case 'x': flags |= F_EXPORT; break;
default: f |= f_bogus; break;
}
exit(EXIT_FAILURE);
}
- /* --- Get the important information --- */
+ /* --- Open the display --- */
dpy = XOpenDisplay(display);
if (!dpy) {
fprintf(stderr, "xscsize: couldn't open display\n");
exit(EXIT_FAILURE);
}
+
+ /* --- Fetch the root window size --- *
+ *
+ * We might need this whatever happens, so go with the flow.
+ */
+
sc = DefaultScreen(dpy);
wd = DisplayWidth(dpy, sc);
ht = DisplayHeight(dpy, sc);
- XCloseDisplay(dpy);
- /* --- Do the output thing --- */
+ /* --- Calculate and produce the necessary output --- *
+ *
+ * If we're meant to report on individual screens then try to collect
+ * information about them using the RANDR extension. If that doesn't
+ * exist, or the version is too ancient, or its otherwise not going to
+ * work, then pretend there's just one screen that's the size of the root
+ * window.
+ */
+
+ if (f & f_multi) {
+#ifdef HAVE_XRANDR
+ if (XRRQueryExtension(dpy, &rrev, &rrerr) &&
+ XRRQueryVersion(dpy, &rrmaj, &rrmin) &&
+ (rrmaj > 1 || (rrmaj == 1 && rrmin >= 2))) {
+ root = RootWindow(dpy, sc);
+ res = XRRGetScreenResources(dpy, root);
+ scr = xmalloc(res->ncrtc*sizeof(*scr)); j = 0;
+ for (i = 0; i < res->ncrtc; i++) {
+ crtc = XRRGetCrtcInfo(dpy, res, res->crtcs[i]);
+ if (crtc->mode) {
+ scr[j].x = crtc->x; scr[j].wd = crtc->width;
+ scr[j].y = crtc->y; scr[j].ht = crtc->height;
+ j++;
+ }
+ XRRFreeCrtcInfo(crtc);
+ }
+ nscr = j;
+ XRRFreeScreenResources(res);
+ } else
+#endif
+ {
+ /* --- The RANDR extension isn't available --- */
+
+ nscr = 1;
+ scr = xmalloc(sizeof(*scr));
+ scr->x = 0; scr->wd = wd;
+ scr->y = 0; scr->ht = ht;
+ }
+
+ /* --- Sort and report the screens --- *
+ *
+ * The chances are good that the screens reported by RANDR aren't in any
+ * especially useful order. Sort them into (my) reading order.
+ */
- print_var("XWIDTH", wd);
- print_var("XHEIGHT", ht);
+ qsort(scr, nscr, sizeof(*scr), compare_screen);
+ print_var("XNSCR", -1, nscr);
+ for (j = 0; j < nscr; j++) {
+ print_var("X", j, scr[j].x);
+ print_var("Y", j, scr[j].y);
+ print_var("WIDTH", j, scr[j].wd);
+ print_var("HEIGHT", j, scr[j].ht);
+ }
+ } else {
+ print_var("XWIDTH", -1, wd);
+ print_var("XHEIGHT", -1, ht);
+ }
+
+ /* --- We're done with the display now --- */
+
+ XCloseDisplay(dpy);
/* --- Done --- */
~mdw / xtoys / commitdiff