FreeModbus LINUXTCP Compile ERROR

/*********************************************************************************
 *                 FreeModbus LINUXTCP Compile ERROR
 * 说明：
 *     想使用FreeModbus TCP在Ubuntu上进行测试，结果其默认没有打开TCP功能。
 *
 *                                              2018-1-2 深圳 南山平山村 曾剑锋
 ********************************************************************************/

一、参考文档：
    1. http://pl.comp.lang.c.narkive.com/3s8TevOZ/problem-z-kompilacj

二、报错信息：
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/demo.c:76: undefined reference to `eMBTCPInit'
    ../../modbus/mb.o: In function `eMBInit':
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:148: undefined reference to `eMBRTUStart'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:149: undefined reference to `eMBRTUStop'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:150: undefined reference to `eMBRTUSend'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:151: undefined reference to `eMBRTUReceive'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:152: undefined reference to `vMBPortClose'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:153: undefined reference to `xMBRTUReceiveFSM'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:154: undefined reference to `xMBRTUTransmitFSM'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:155: undefined reference to `xMBRTUTimerT35Expired'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:157: undefined reference to `eMBRTUInit'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:162: undefined reference to `eMBASCIIStart'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:163: undefined reference to `eMBASCIIStop'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:164: undefined reference to `eMBASCIISend'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:165: undefined reference to `eMBASCIIReceive'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:166: undefined reference to `vMBPortClose'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:167: undefined reference to `xMBASCIIReceiveFSM'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:168: undefined reference to `xMBASCIITransmitFSM'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:169: undefined reference to `xMBASCIITimerT1SExpired'
    /home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP/../../modbus/mb.c:171: undefined reference to `eMBASCIIInit'
    collect2: error: ld returned 1 exit status
    Makefile:58: recipe for target 'tcpmodbus' failed
    make: *** [tcpmodbus] Error 1

三、解决办法：
    1. modified the file "freemodbus/modbus/include/mbconfig.h"
    2. find the under code
           /*! \brief If Modbus ASCII support is enabled. */
           #define MB_ASCII_ENABLED ( 1 )
           /*! \brief If Modbus RTU support is enabled. */
           #define MB_RTU_ENABLED ( 1 )
           /*! \brief If Modbus TCP support is enabled. */
           #define MB_TCP_ENABLED ( 0 )
           /*! \brief The character timeout value for Modbus ASCII.
       change into
           #define MB_ASCII_ENABLED ( 0 )
           #define MB_RTU_ENABLED ( 0 )
           #define MB_TCP_ENABLED ( 1 )

四、Compile Output：
    root@localhost:/home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP# make
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o demo.o -c demo.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o port/portother.o -c port/portother.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o port/portevent.o -c port/portevent.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o port/porttcp.o -c port/porttcp.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o ../../modbus/mb.o -c ../../modbus/mb.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o ../../modbus/tcp/mbtcp.o -c ../../modbus/tcp/mbtcp.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o ../../modbus/functions/mbfunccoils.o -c ../../modbus/functions/mbfunccoils.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o ../../modbus/functions/mbfuncdiag.o -c ../../modbus/functions/mbfuncdiag.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o ../../modbus/functions/mbfuncholding.o -c ../../modbus/functions/mbfuncholding.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o ../../modbus/functions/mbfuncinput.o -c ../../modbus/functions/mbfuncinput.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o ../../modbus/functions/mbfuncother.o -c ../../modbus/functions/mbfuncother.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o ../../modbus/functions/mbfuncdisc.o -c ../../modbus/functions/mbfuncdisc.c
    gcc -g -Wall -Iport -I../../modbus/rtu -I../../modbus/ascii -I../../modbus/include -I../../modbus/tcp -pthread -o ../../modbus/functions/mbutils.o -c ../../modbus/functions/mbutils.c
    gcc demo.o port/portother.o port/portevent.o port/porttcp.o ../../modbus/mb.o ../../modbus/tcp/mbtcp.o ../../modbus/functions/mbfunccoils.o ../../modbus/functions/mbfuncdiag.o ../../modbus/functions/mbfuncholding.o ../../modbus/functions/mbfuncinput.o ../../modbus/functions/mbfuncother.o ../../modbus/functions/mbfuncdisc.o ../../modbus/functions/mbutils.o   -lpthread  -o tcpmodbus
    root@localhost:/home/zengjf/freemodbus/freemodbus-v1.5.0/demo/LINUXTCP#