libxml2的安装：
1.安装包下载地址：http://xmlsoft.org/，我下载的地方是http://xmlsoft.org/sources/old/
2.下载好压缩包后，对其进行解压，解压的命令是：sudo tar xvzf libxml2-2.7.1.tar.gz
3.配置，编译安装过程：
解压好之后，进入解压好的文件夹中：
cd libxml2-2.7.1
（默认路径安装）
sudo ./configure
sudo make
sudo make install
（自己设置安装路径）
或则
sudo ./configure --prefix /home/user/myxml/xmlinst
sudo make
sudo make install
export PATH=/home/user/myxml/xmlinst/bin:$PATH
我是按照默认路径安装的，因此下面的示例编译方法都是针对默认路径的。
libxml2经典应用示例xmlCreator.cpp：
1 #include <stdio.h> 2 #include <libxml/parser.h> 3 #include <libxml/tree.h> 4 5 int main(int argc,char **argv) 6 { 7 xmlDocPtr doc = NULL;/*document pointer*/ 8 xmlNodePtr root_node = NULL,node = NULL,node1 = NULL;/*node pointers*/ 9 //Creates a new document,a node and set it as a root node 10 doc = xmlNewDoc(BAD_CAST"1.0"); 11 root_node = xmlNewNode(NULL,BAD_CAST"root"); 12 xmlDocSetRootElement(doc,root_node); 13 //creates a new node,which is "attached" as child node of root_node node. 14 xmlNewChild(root_node,NULL,BAD_CAST"node1",BAD_CAST"content of node1"); 15 16 //xmlNewProp()creates attributes,which is "attached" to an node. 17 node = xmlNewChild(root_node,NULL,BAD_CAST"node3",BAD_CAST"node has attributes"); 18 xmlNewProp(node,BAD_CAST"attribute",BAD_CAST"yes"); 19 20 //Here goes another way to create nodes. 21 node = xmlNewNode(NULL,BAD_CAST"node4"); 22 node1 = xmlNewText(BAD_CAST"other way to create content"); 23 24 xmlAddChild(node,node1); 25 xmlAddChild(root_node,node); 26 27 //Dumping document to stdio or file 28 xmlSaveFormatFileEnc(argc > 1 ? argv[1]:"-",doc,"UTF-8",1); 29 30 /*free the document*/ 31 xmlFreeDoc(doc); 32 xmlCleanupParser(); 33 xmlMemoryDump();//debug memory for regression tests 34 35 return 0; 36 }
编译过程：此处是cpp文件，因此是，g++ xmlCreator.cpp -o xmlCreator -I /usr/local/include/libxml2 -L /usr/local/lib -lxml2
如果是c文件，则应该改为：gcc xmlCreator.cpp -o xmlCreator -I /usr/local/include/libxml2 -L /usr/local/lib -lxml2
******-I 后接头文件目录 -L后接lib库目录
......$ gcc xmlCreator.cpp -o xmlCreator -I /usr/local/include/libxml2 -lxml2 /tmp/ccPeKBRE.o:(.eh_frame+0x12): undefined reference to `__gxx_personality_v0' collect2: ld returned 1 exit status
......$ g++ xmlCreator.cpp -o xmlCreator -I /usr/local/include/libxml2 -lxml2 ---------------ok
因此，出现这种错误的时候，要注意看是不是编译器用错了，用gcc编译C程序，用g++编译C++程序，对号入座就没有问题了。
生成xmlCreator文件后，运行结果如下：
1 <?xml version="1.0" encoding="UTF-8"?> 2 <root> 3 <node1>content of node1</node1> 4 <node3 attribute="yes">node has attributes</node3> 5 <node4>other way to create content</node4> 6 </root>
到此，一个使用libxml2库创建xml文件的简单例子就讲完了。。。。。。