void serial_write(int fd, const char *data, size_t len) ssize_t written = write(fd, data, len); if (written < 0) perror("write"); else printf("Wrote %ld bytes\n", written);
int main() const char *device = "/dev/ttyUSB0"; // Change to your port speed_t baud = B115200;
// Wait for response char response[256]; serial_read(fd, response, sizeof(response));
gcc -o serial_example serial_example.c (you may need sudo for /dev/ttyUSB0 ):
// Send a command const char *cmd = "AT\r\n"; serial_write(fd, cmd, strlen(cmd));
Here’s a practical for serial port communication on Linux/POSIX systems. It demonstrates opening, configuring, reading, writing, and closing a serial port. Serial Port Communication in C – Complete Example #include <stdio.h> // Standard I/O #include <stdlib.h> // Exit functions #include <fcntl.h> // File control (open) #include <termios.h> // Terminal I/O (serial config) #include <unistd.h> // POSIX (read, write, close) #include <string.h> // String operations int serial_open(const char *device, speed_t baud) IXOFF