A while back I put together a crappy C monitor, which I still use to the day.
Find the .c attached, compile with -lX11 as normal, peruse at will.
Cheers,
Rafa.
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <sys/types.h>
#include <regex.h>
#include <unistd.h>
#include <signal.h>
#include <string.h>
#include <Xutil.h>
#include <Xatom.h>
#define BATTERY "BAT1"
#define BATT_INFO_PATH "/proc/acpi/battery/"BATTERY"/info"
#define BATT_STATE_PATH "/proc/acpi/battery/"BATTERY"/state"
#define BATT_FULL_REGEX "^last full capacity:[ ]+([0-9]*) .*$"
#define BATT_CUR_REGEX "^remaining capacity:[ ]+([0-9]*) .*$"
#define DATE_FORMAT "%H:%M (%Z) - %a %d.%m.%Y"
#define BUFFER_SIZE 4096
#define STATUS_SIZE 256
static char *buf;
static regex_t *batt_full_re, *batt_cur_re;
static Display *dpy;
static Window root;
static XTextProperty name;
void update_status(char *c) {
name.value=(unsigned char*)c;
name.nitems=strlen(c);
XSetWMName(dpy, root, &name);
XSync(dpy, False);
}
void cleanup(void) {
regfree(batt_full_re);
regfree(batt_cur_re);
free(buf);
}
void die(int unused) {
update_status("dwmrc died!");
exit(EXIT_FAILURE);
}
int read_batt(const char *batt_path, const regex_t *batt_re) {
FILE *f;
int batt_total = -1;
regmatch_t result_re[2];
f = fopen(batt_path, "r");
fread(buf, 1, BUFFER_SIZE, f);
regexec(batt_re, buf, 2, result_re, 0);
if(result_re[1].rm_so != -1 && result_re[1].rm_eo != -1) {
buf[result_re[1].rm_eo]='\0';
batt_total = atoi(buf+result_re[1].rm_so);
}
fclose(f);
return batt_total;
}
int main(int argc, char **argv) {
time_t cur_t;
struct tm *cur_lt;
char *status;
int batt_full, batt_cur;
int n;
if( !(dpy = XOpenDisplay(NULL)) ||
!(buf = calloc(1, sizeof(char)*BUFFER_SIZE)) ||
!(status = calloc(1, sizeof(char)*STATUS_SIZE)) ||
!(batt_full_re = calloc(1, sizeof(regex_t))) ||
!(batt_cur_re = calloc(1, sizeof(regex_t))) ) die(0);
regcomp(batt_full_re, BATT_FULL_REGEX, REG_EXTENDED|REG_NEWLINE);
regcomp(batt_cur_re, BATT_CUR_REGEX, REG_EXTENDED|REG_NEWLINE);
root = RootWindow(dpy, DefaultScreen(dpy));
name.encoding=XA_STRING;
name.format=8;
signal(SIGINT, die);
signal(SIGILL, die);
signal(SIGTERM, die);
while(1) {
batt_full=read_batt(BATT_INFO_PATH, batt_full_re);
batt_cur =read_batt(BATT_STATE_PATH, batt_cur_re);
if(batt_full > 0 && batt_cur >= 0) n=snprintf(status, STATUS_SIZE, "%3d%% -- ", (100*batt_cur/batt_full));
else n=snprintf(status, STATUS_SIZE, " NAN -- ");
cur_t = time(NULL);
cur_lt = localtime(&cur_t);
strftime(&status[n], STATUS_SIZE-n, DATE_FORMAT, cur_lt);
update_status(status);
sleep(10);
}
return EXIT_SUCCESS;
}
