linux使用pkg-config写简单的Makefile
将要编译的代码如下, 名字是add_node.c
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <libxml/xmlmemory.h>
#include <libxml/parser.h>
#include "null.h"
void parseStory (xmlDocPtr doc, xmlNodePtr cur, char *keyword)
{
xmlNewTextChild (cur, NULL, "keyword", keyword);
cur = cur->xmlChildrenNode;
while (cur != NULL)
{
printf("cur->name: %s\n", cur->name);
cur = cur->next;
}
return;
}
xmlDocPtr parseDoc(char *docname, char *keyword)
{
xmlDocPtr doc;
xmlNodePtr cur;
printf("before xmlParseFile->docname: %s\n", docname);
doc = xmlParseFile(docname);
printf("after xmlParseFile->docname: %s\n", docname);
if (doc == NULL )
{
fprintf(stderr,"Document not parsed successfully. \n");
return (NULL);
}
cur = xmlDocGetRootElement(doc);
if (cur == NULL)
{
fprintf(stderr,"empty document\n");
xmlFreeDoc(doc);
return (NULL);
}
if (xmlStrcmp(cur->name, (const xmlChar *) "story"))
{
fprintf(stderr,"document of the wrong type, root node != story\n");
xmlFreeDoc(doc);
return (NULL);
}
cur = cur->xmlChildrenNode;
while (cur != NULL)
{
if ((!xmlStrcmp(cur->name, (const xmlChar *)"storyinfo")))
{
parseStory (doc, cur, keyword);
}
cur = cur->next;
}
return(doc);
}
int main(int argc, char **argv)
{
char *docname;
char *keyword;
xmlDocPtr doc;
if (argc <= 2)
{
printf("Usage: %s docname, keyword\n", argv[0]);
return(0);
}
printf("argv[0]: %s\n", argv[0]);
docname = argv[1];
printf("argv[1]: %s\n", argv[1]);
keyword = argv[2];
printf("argv[2]: %s\n", argv[2]);
doc = parseDoc (docname, keyword);
if (doc != NULL)
{
xmlSaveFormatFile (docname, doc, 0);
xmlFreeDoc(doc);
}
return (1);
}
为了引导读者在使用Makefile编译更多的文件，写一个null.h，如下：
#include <time.h>
/*aaaa*/
实际上它是一个不干什么的公务员，只是充个名。
下面是Makefile的内容:
LIBXML_INC=$(shell pkg-config --cflags libxml-2.0)
CFLAGS += $(LIBXML_INC)
LIBXML_LIBS=$(shell pkg-config --libs libxml-2.0)
LIBS += $(LIBXML_LIBS)
aaa:add_node.c null.h
$(CC) -o aaa $(CFLAGS) $(LIBS) $<
大家只要稍微留意一下会发现网上有不少pkg-config的介绍，这里就用到了他，用它的目的的使你的程序具有通用性，不至于只能在你的一亩三分地跑起来。使用make之后他便输出aaa,你输入：./aaa 1.xml suibianxieshenme ，边能发现1.xml增加了一个节点。
1.xml的格式如下，我已经运行几次了，所以看起来怪怪的:
<?xml version="1.0"?>
<story>
<storyinfo>
<author>John Fleck</author>
<datewritten>June 2, 2002</datewritten>
<keyword>example keyword</keyword>
<keyword>menj</keyword><keyword>mengjun</keyword></storyinfo>
<body>
<headline>This is the headline</headline>
<para>This is the body text.</para>
</body>
<reference uri="mengj" address="mengj" institute="mengj"/></story>
另外如果你就想用（刚开始我也想）包含pkg-congfig的gcc命令编译add_node.c，那你就使用下面的命令：
gcc -g add_node.c -o add_node `pkg-config "libxml-2.0" --cflags --libs`
