Linux编译sip库及第一个demo

对于Linux，我属于半路出家。编译一个sip，也是一波三折；步骤一一记录如下

开发环境：ubuntu

1.下载sip库：libeXosip2-3.6.0.tar.gz  libosip2-3.6.0.tar.gz

下载地址：http://download.savannah.gnu.org/releases/exosip/

2.编译

解压以后，出现两个文件夹：

然后进行编译，一句一句执行，先切换到目标文件夹，在configure，在make，在make install，如下：

cd libosip2-3.6.0 
./configure
make
make install

cd libeXosip2-3.6.0
./configure --disable-openssl
make
make install

3.一个简单的demo

main.cpp

#include <eXosip2/eXosip.h>

int main()
{
	int i=0;
	i=eXosip_init();
	if(i!=0)
          return -1;
	printf("=========  %s",eXosip_get_version());//打印当前sip库的版本号
	getchar();
	return 0;
}

3.1编译(调用sip动态库)：

g++ main.cpp -o main -leXosip2 -losip2  -losipparser2

运行（因为sip编译完的动态库在/usr/local/lib目录下）：

LD_LIBRARY_PATH=/usr/local/lib ./main

3.2编译(调用sip静态库)：

编译完的sip库的静态库也在/usr/local/lib目录下，我把他们考了出来，放在了工程目录的lib目录下

然后编译

g++ -pthread src/main.cpp -o main -L./lib -leXosip2 -losip2  -losipparser2 -lresolv

执行：

./main

运行结果

完成！

==============================================分割线===================================================

看上去好像很简单？但是却废了咱不少功夫。

首先，是编译，自然是想到：g++ main.cpp -o main   就OK了，可结果呢，报错：找不到函数undefined reference to `eXosip_init'

其次，是运行，直接

./main

不行，报错：./main: error while loading shared libraries: libeXosip2.so.7: cannot open shared object file: No such file or directory

找动态库...

再次，好吧，解决了动态库；就想，为何不能用静态库呢，多方便哪？代价就是又要花时间来研究一番

网上看了一番，知道了g++ -L <目录>  是加载目录下的说有静态库，于是来了一句

g++ src/main.cpp -o main -L./lib -leXosip2 -losip2  -losipparser2

结果又是一顿报错：

./lib/libeXosip2.a(eXutils.o): In function `_eXosip_dnsutils_srv_lookup':
/jiang/workspace/siplib/libeXosip2-3.6.0/src/eXutils.c:3040: undefined reference to `__res_query'
/jiang/workspace/siplib/libeXosip2-3.6.0/src/eXutils.c:3056: undefined reference to `__dn_expand'
/jiang/workspace/siplib/libeXosip2-3.6.0/src/eXutils.c:3074: undefined reference to `__dn_expand'
/jiang/workspace/siplib/libeXosip2-3.6.0/src/eXutils.c:3159: undefined reference to `__dn_expand'
./lib/libeXosip2.a(eXutils.o): In function `eXosip_dnsutils_naptr_lookup':
/jiang/workspace/siplib/libeXosip2-3.6.0/src/eXutils.c:3252: undefined reference to `__res_query'
/jiang/workspace/siplib/libeXosip2-3.6.0/src/eXutils.c:3284: undefined reference to `__dn_expand'
/jiang/workspace/siplib/libeXosip2-3.6.0/src/eXutils.c:3314: undefined reference to `__dn_expand'
/jiang/workspace/siplib/libeXosip2-3.6.0/src/eXutils.c:3397: undefined reference to `__dn_expand'
./lib/libosip2.a(port_sema.o): In function `osip_sem_init':
/jiang/workspace/siplib/libosip2-3.6.0/src/osip2/port_sema.c:170: undefined reference to `sem_init'
./lib/libosip2.a(port_sema.o): In function `osip_sem_destroy':
/jiang/workspace/siplib/libosip2-3.6.0/src/osip2/port_sema.c:182: undefined reference to `sem_destroy'
./lib/libosip2.a(port_sema.o): In function `osip_sem_post':
/jiang/workspace/siplib/libosip2-3.6.0/src/osip2/port_sema.c:193: undefined reference to `sem_post'
./lib/libosip2.a(port_sema.o): In function `osip_sem_wait':
/jiang/workspace/siplib/libosip2-3.6.0/src/osip2/port_sema.c:202: undefined reference to `sem_wait'
./lib/libosip2.a(port_sema.o): In function `osip_sem_trywait':
/jiang/workspace/siplib/libosip2-3.6.0/src/osip2/port_sema.c:211: undefined reference to `sem_trywait'
./lib/libosip2.a(port_thread.o): In function `osip_thread_create':
/jiang/workspace/siplib/libosip2-3.6.0/src/osip2/port_thread.c:55: undefined reference to `pthread_create'
./lib/libosip2.a(port_thread.o): In function `osip_thread_join':
/jiang/workspace/siplib/libosip2-3.6.0/src/osip2/port_thread.c:76: undefined reference to `pthread_join'
collect2: ld returned 1 exit status

再找...看到报错信息里面，pthread_create，线程？果然放入百度，出来答案，立马加入-pthread，支持多线程。

还有一堆报错，再加入-lresolv；

至此，告一段落。