How to list serial ports in C?

Introduction

This page explains how to scan serial ports using the Serialib library. Serialib is a cross-platform library written in C++.

• No dependencies
• Only two files (serialib.h and serialib.cpp)
• Cross-platform

The library has been tested on Windows and Linux. This project has been developed with Qt Creator and succesfully compile with:

• gcc on Linux
• MinGW on Windows The library should work on Mac OS and can compiled with others IDE.

Scanning ports

The best options to get the list of available serial ports is to open each device and check the status of the function openDevice:

// Test each port between COM1 and COM99 on Windows and between /dev/ttyS0 and /dev/ttyS99 on Linux
for (int i=1;i<99;i++)
{
    // Prepare the port name (Windows)
    #if defined (_WIN32) || defined( _WIN64)
        sprintf (device_name,"\\\\.\\COM%d",i);
    #endif

    // Prepare the port name (Linux)
    #ifdef __linux__
        sprintf (device_name,"/dev/ttyACM%d",i-1);
    #endif

    // try to connect to the device
    if (device.openDevice(device_name,115200)==1)
    {
        printf ("Device detected on %s\n", device_name);
        // Close the device before testing the next port
        device.closeDevice();
    }
}

See also

• Convert bauds to bits per second
• Convert bauds to bytes per second
• C++ cross-platform RS232 serial communication library
• Most common baud rates table
• What are the most used baud rates?

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