How to compile libserial on linux?

Question

My program needs to communicate with a serial device. I am developing it on Ubuntu 14.04 LTS. I found libserial, and tried to use it, but it does not compile. I downloaded, compiled and installed v0.6.0rc2. Yeah, it is a rc, but it is more popular on sourceforge and the stable releases are very old. If you know a better library, please tell it to me in the comments.

The code given below as per the docs doesnot compile:

#include <SerialStream.h>
//
using namespace LibSerial ;
main()
{
    SerialStream my_serial_stream ;
    //
    // Open the serial port for communication.
    //
    my_serial_stream.Open( "/dev/ttyS0" ) ;

}

This is the error I get:

dalton@dalton-SVF14212SNW:~$ g++ test.cpp
/tmp/ccyWIbXN.o: In function `main':
test.cpp:(.text+0x17): undefined reference to `LibSerial::SerialStream::SerialStream()'
test.cpp:(.text+0x6d): undefined reference to `LibSerial::SerialStream::Open(std::string, std::_Ios_Openmode)'
test.cpp:(.text+0x9a): undefined reference to `LibSerial::SerialStream::~SerialStream()'
test.cpp:(.text+0xd6): undefined reference to `LibSerial::SerialStream::~SerialStream()'
collect2: error: ld returned 1 exit status

I've changed the line in question to my_serial_stream.Open( "/dev/ttyS0" , ios::out ) ; and added namespace std. Now I get this error:

dalton@dalton-SVF14212SNW:~$ g++ test.cpp
/tmp/ccUhSQVA.o: In function `main':
test.cpp:(.text+0x17): undefined reference to `LibSerial::SerialStream::SerialStream()'
test.cpp:(.text+0x5f): undefined reference to `LibSerial::SerialStream::Open(std::string, std::_Ios_Openmode)'
test.cpp:(.text+0x8c): undefined reference to `LibSerial::SerialStream::~SerialStream()'
test.cpp:(.text+0xc8): undefined reference to `LibSerial::SerialStream::~SerialStream()'
collect2: error: ld returned 1 exit status

score 1 · Accepted Answer · edited May 23 '17 at 11:58

You need to link the library to your code.

try using

g++ test.cpp -L<PATH_TO_LIB_SERIAL_LIBRARY_DIR> -lserial

Lets assume you installed libserial in /usr/local/lib (libserial.a or libserial.so is in /usr/local/lib) you'd use the following command to compile and link your program

g++ test.cpp -L/usr/local/lib -lserial

The error output you posted, shows that the error occurred during the linking phase.

See What is an undefined reference/unresolved external symbol error and how do I fix it?

for more information on what may cause the the linking errors.

In this case it looks like you didn't link to the library.

How to compile libserial on linux?

1 Answers1