whole 1st line done basically

include/lcd.h

@@ -4,6 +4,7 @@
 #define LCD_LINES 4
 #define LCD_COLS 40
 
+#include <stdbool.h>
 #include <stdint.h>
 
 struct lcd_t {
@@ -24,7 +25,7 @@ void lcd_set_custom_char(struct lcd_t* lcd, uint8_t index, const lcd_glyph_t* gl
 void lcd_write_str(struct lcd_t* lcd, const char* str, uint8_t len);
 void lcd_write_str_pos(struct lcd_t* lcd, const char* str, uint8_t len, uint8_t posX, uint8_t posY);
 void lcd_write_buf(struct lcd_t* lcd, uint8_t row, uint8_t col, const char* str);
-int lcd_writef(struct lcd_t *lcd, uint8_t offset, const char *fmt, ...);
+void lcd_writef(struct lcd_t *lcd, uint8_t x, uint8_t y, const char *fmt, ...)  __attribute__((format(printf, 4, 5)));
 void lcd_clear_buf(struct lcd_t* lcd);
 void lcd_flush_buf(struct lcd_t* lcd);
 char lcd_bar(struct lcd_t* lcd, uint8_t char_id, double value);

include/sys.h

@@ -0,0 +1,12 @@
+#ifndef LINUXSMARTIE_SYS_H
+#define LINUXSMARTIE_SYS_H
+
+struct time_date_t {
+	char date[12];
+	char time[9];
+};
+
+void sys_get_time(struct time_date_t *td);
+void sys_get_load_avg(double *load_avg);
+
+#endif //LINUXSMARTIE_SYS_H

src/sys.c

@@ -0,0 +1,18 @@
+#include "sys.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+
+void sys_get_time(struct time_date_t *td) {
+	constexpr char months[][4] = {"sty", "lut", "mar", "kwi", "maj", "cze", "lip", "sie", "wrz", "paz", "lis", "gru"};
+	constexpr char wdays[][4] = {"Nie", "Pon", "Wto", "Sro", "Czw", "Pia", "Sob"};
+	const time_t t = time(nullptr);
+	const struct tm *tm = localtime(&t);
+	snprintf(td->time, sizeof(td->time), "%02d:%02d:%02d", tm->tm_hour, tm->tm_min, tm->tm_sec);
+	snprintf(td->date, sizeof(td->date), "%s, %02d %s", wdays[tm->tm_wday], tm->tm_mday, months[tm->tm_mon]);
+}
+
+void sys_get_load_avg(double *load_avg) {
+	getloadavg(load_avg, 3);
+}