Added README file.

[dwm-status] / dwmstatus.c

/*
 * SGK version of dwmstatus by 20h.
 */

#define _BSD_SOURCE
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <time.h>
#include <X11/Xlib.h>

static Display *dpy;

char *
smprintf(char *fmt, ...)
{
	va_list fmtargs;
	char *ret;
	int len;

	va_start(fmtargs, fmt);
	len = vsnprintf(NULL, 0, fmt, fmtargs);
	va_end(fmtargs);

	ret = malloc(++len);
	if (ret == NULL) {
		perror("malloc");
		exit(1);
	}

	va_start(fmtargs, fmt);
	vsnprintf(ret, len, fmt, fmtargs);
	va_end(fmtargs);

	return ret;
}

char *
mktimes(char *fmt, char *tzname)
{
	char buf[129];
	time_t tim;
	struct tm *timtm;

	setenv("TZ", tzname, 1);
	tim = time(NULL);
	timtm = localtime(&tim);
	if (timtm == NULL)
		return smprintf("");

	if (!strftime(buf, sizeof(buf)-1, fmt, timtm)) {
		fprintf(stderr, "strftime == 0\n");
		return smprintf("");
	}

	return smprintf("%s", buf);
}

void
setstatus(char *str)
{
	XStoreName(dpy, DefaultRootWindow(dpy), str);
	XSync(dpy, False);
}

char *
loadavg(void)
{
	double avgs[3];

	if (getloadavg(avgs, 3) < 0)
		return smprintf("");

	return smprintf("%.2f", avgs[0]);
}

int
main(void)
{
	char *load, *datetime, *status;

	if (!(dpy = XOpenDisplay(NULL))) {
		fprintf(stderr, "dwmstatus: cannot open display.\n");
		return 1;
	}

	for (;;sleep(5)) {
		load = loadavg();
		datetime = mktimes("%a %d %b %Y ][ %H:%M", "America/Los_Angeles");

		status = smprintf("[ %s ][ %s ]", load, datetime);
		setstatus(status);

		free(load);
		free(datetime);
		free(status);
	}

	XCloseDisplay(dpy);

	return 0;
}