diff --git a/bmon.c b/bmon.c
index fb6f20e..12dbccd 100644
--- a/bmon.c
+++ b/bmon.c
@@ -4,30 +4,56 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <dirent.h>
-#include <poll.h>
 #include <errno.h>
 #include <string.h>
 #include <unistd.h>
-
-//char *bat_power_path = "/sys/class/power_supply/BAT1/energy_now";
-//char *bat_capacity_path =  "/sys/class/power_supply/BAT1/capacity";
+#include <signal.h>
 
 const char *bat_base_path = "/sys/class/power_supply/";
+int dead = 0;
 
 void usage (void)
 {
-	printf("usage: bmon [-w]\n");
+	printf("usage: bmon [-h] [-w] [-f file] [-t interval]\n");
+}
+
+void int_handler (int signum)
+{
+        dead = 1;
 }
 
 int main (int argc, char *argv[])
 {
+	/* Handle SIGINT */
+        dead = 0;
+        struct sigaction action;
+        memset(&action, 0, sizeof(action));
+        action.sa_handler = int_handler;
+        sigaction(SIGINT, &action, NULL);
+
 	int wflag = 0;
+	int wait_time = 10;
+	int fflag = 0;
+	char ofile_path[256];
+
 	int opc;
-	while ((opc = getopt(argc, argv, "w")) != -1) {
+	while ((opc = getopt(argc, argv, "hwf:t:")) != -1) {
 		switch (opc) {
 		case 'w':
 			wflag = 1;
 			break;
+		case 'f':
+			fflag = 1;
+			strncpy(ofile_path, optarg, 255);
+			break;
+		case 't':
+			wait_time = atoi(optarg);
+			if (wait_time < 0) {
+				usage();
+				exit(1);
+			}
+			break;
+		case 'h':
 		default: /* '?' */
 			usage();
 			exit(1);
@@ -41,8 +67,8 @@ int main (int argc, char *argv[])
 		perror("error opening base directory");
 	
 	struct dirent *ent = NULL;
-	int *fd_list = NULL;
-	int fd_num = 0;
+	FILE **fp_list = NULL;
+	int fp_num = 0;
 	for (;;) {
 		errno = 0;
 		if (!(ent = readdir(bdir))) {
@@ -54,7 +80,7 @@ int main (int argc, char *argv[])
 		if (!strstr(ent->d_name, "BAT1"))
 			continue;
 
-		int fd;
+		FILE *fp;
 		char path[sizeof(bat_base_path) + 256 + 64];
 		strcpy(path, bat_base_path);
 		strcat(path, ent->d_name);
@@ -62,22 +88,57 @@ int main (int argc, char *argv[])
 			strcat(path, "/energy_now");
 		else strcat(path, "/capacity");
 
-		if ((fd = open(path, O_RDONLY | O_NONBLOCK)) != -1) {
-			int *tmp = NULL;
-			tmp = realloc(fd_list, sizeof(int) * (fd_num + 1));
+		if ((fp = fopen(path, "r"))) {
+			FILE **tmp = NULL;
+			tmp = realloc(fp_list, sizeof(FILE *) * (fp_num + 1));
 			if (!tmp)
 				perror("failed realloc");
-			fd_list = tmp;
-			fd_list[fd_num] = fd;
-			fd_num++;
+			fp_list = tmp;
+			fp_list[fp_num++] = fp;
 		} else printf("err: %s\n", strerror(errno));
 				
 	}
 	closedir(bdir);
-	if (!fd_num)
+	if (!fp_num) {
 		printf("no files were opened\n");
+		goto main_end;
+	}
+	
+	FILE * ofile_ptr;
+	if (fflag) {
+		if (!(ofile_ptr = fopen(ofile_path, "w"))) {
+			char * tmp = malloc(1024);
+			snprintf(tmp, 1024, "could not open %s", ofile_path);
+			perror(tmp);
+		}
+	}
+
+	long long elapsed_time = 0;
+	char buf[64];
+	for (; !dead ; sleep(wait_time)) {
+		for (int i = 0; i < fp_num; i++) {
+			freopen(NULL, "r", fp_list[i]);
+			fgets(buf, 64, fp_list[i]);
+			buf[strcspn(buf, "\r\n")] = 0;
+			if (fflag)
+				fprintf(ofile_ptr, "%s\t", buf);
+			else
+				printf("%s\t", buf);
+		}
+		if (fflag) {
+			fprintf(ofile_ptr, "%lld\n", elapsed_time);
+			fflush(ofile_ptr);
+		} else { 
+			printf("%lld\n", elapsed_time);
+		}
+		elapsed_time += wait_time;
+	}
 	
-	for (int i = 0; i < fd_num; i++)
-		close(fd_list[i]);
+	main_end:
+	if (fflag)
+		fclose(ofile_ptr);
+	for (int i = 0; i < fp_num; i++)
+		fclose(fp_list[i]);
+	free(fp_list);
 	return 0;
 }