added devel folder..

devel/xxx/clientd/Makefile

@@ -0,0 +1,7 @@
+all: client
+
+client: main.c
+	gcc -std=gnu99 main.c serial.c -o client
+
+run: client
+	./client /dev/ttyUSB0 9600

devel/xxx/clientd/main.c

@@ -0,0 +1,37 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <unistd.h>
+
+#include "serial.h"
+
+int main(int argc, char const *argv[])
+{
+	if (argc < 2) { fprintf(stderr, "Missing parameter <device>\n"); return 1; }
+
+	int baud = 9600;
+	if (argc == 3) sscanf(argv[2], "%d", &baud);
+
+	int fd = serial_open(argv[1], baud);
+
+	// Wait for the Arduino to start
+	usleep(1500000);
+
+	// Redirecting stdin/stdout to arduino
+	while(1) {
+		char buf[1];
+		if (fread(buf, 1, 1, stdin) > 0) {
+			serial_write(fd, buf[0]);
+			fflush(stdout);
+		}
+
+		char c;
+		c = serial_read(fd, 10);
+		if (c > 0) {
+			putchar(c);
+			fflush(stdout);
+		}
+	}
+}
+

devel/xxx/clientd/serial.c

@@ -0,0 +1,89 @@
+#define _POSIX_SOURCE
+#define _GNU_SOURCE
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <termios.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "serial.h"
+
+
+/** Open a serial port */
+int serial_open(const char* port, const unsigned int baud)
+{
+	int fd = open(port, O_RDWR | O_NONBLOCK);
+
+	struct termios tio;
+	memset(&tio, 0, sizeof(tio));
+
+	speed_t bd = baud;
+	switch(bd) {
+		case 1200: bd = B1200; break;
+		case 1800: bd = B1800; break;
+		case 2400: bd = B2400; break;
+		case 4800: bd = B4800; break;
+		case 9600: bd = B9600; break;
+		case 19200: bd = B19200; break;
+		case 38400: bd = B38400; break;
+	}
+
+	tio.c_cflag = bd | CS8 | CLOCAL | CREAD | CRTSCTS;
+	tio.c_iflag = IGNPAR;
+
+	tcflush(fd, TCIFLUSH);
+	tcsetattr(fd, TCSANOW, &tio);
+	return fd;
+}
+
+
+/** Close a serial port */
+int serial_close(int fd)
+{
+	return close(fd);
+}
+
+
+/** Write a byte. Returns false on failure */
+int serial_write(int fd, uint8_t b)
+{
+	return write(fd, &b, 1);
+}
+
+
+int serial_puts(int fd, const char* str)
+{
+	int len = strlen(str);
+	return write(fd, str, len);
+}
+
+
+uint8_t serial_read(int fd, int timeout)
+{
+	uint8_t b[1];
+	do {
+		int n = read(fd, b, 1);
+		if (n == -1) return -1;
+		if (n == 0) {
+			usleep(1 * 1000);  // wait 1 ms
+			timeout--;
+			continue;
+		}
+		return b[0];
+	} while(timeout > 0);
+	return -1;
+}
+
+
+int serial_flush(int fd)
+{
+    sleep(2);
+    return tcflush(fd, TCIOFLUSH);
+}

devel/xxx/clientd/serial.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <stdint.h>
+
+
+/** Open a serial port */
+int serial_open(const char* port, const unsigned int baud);
+
+
+/** Close a serial port */
+int serial_close(int fd);
+
+
+/** Write a byte. Returns false on failure */
+int serial_write(int fd, uint8_t b);
+
+
+/** Send a string */
+int serial_puts(int fd, const char* str);
+
+
+/** Read a byte */
+uint8_t serial_read(int fd, int timeout);
+
+
+/** Flush */
+int serial_flush(int fd);