想用C语言写个采集程序，涉及到http相关的东西，找了找，有现成的libghttp库。
libghttp库的官方网址google一下第一条结果一般就是的：http://lfs.linuxsir.org/htdocs/blfscvs/gnome/libghttp.html

将源码包下载下来，进入例行安装流程：
1、解压

# tar -xzvf libghttp-1.0.9.tar.gz
# cd libghttp-1.0.9

2、安装

./configure
make
make install

安装过种中小插曲：
在执行./configure命令的时候报错：

checking host system type... Invalid configuration `x86_64-unknown-linux-gnu': machine `x86_64-unknown' not recognized
 checking build system type... Invalid configuration `x86_64-unknown-linux-gnu': machine `x86_64-unknown' not recognized
 checking for ranlib... ranlib
checking for ld used by GCC... /usr/bin/ld
checking if the linker (/usr/bin/ld) is GNU ld... yes
checking for BSD-compatible nm... /usr/bin/nm -B
checking whether ln -s works... yes
updating cache ./config.cache
ltconfig: you must specify a host type if you use `--no-verify'
Try `ltconfig --help' for more information.
configure: error: libtool configure failed

听说在32位操作系统上一般不会有这样的错误，在64位系统上比较常见，原因是软件自身的config.guess和config.sub文件有问题，从系统中复制这两个文件到软件目录覆盖一下重新./configure就可以了(如果不知道这两个文件在哪里，用find查找一下就OK了)：

# 首先查找一下config.guess和config.sub文件的目录
find / -name config.guess
find / -name config.sub

# 将查找出来的文件随便选择一个覆盖到软件目录
cp /usr/share/automake-1.11/config.guess .
cp /usr/share/automake-1.11/config.sub .

下面是用libghttp搞了一个测试代码，成功编译和运行，证明libhttp安装成功啦：

#include<libghttp.h>
#include<sthio.h>

main()
{
        // This is the http request object
        ghttp_request *request = NULL;
        // Allocate a new empty request object
        request = ghttp_request_new();
        // Set the URI for the request object
        ghttp_set_uri(request, "http://www.phpjiayuan.com/");
        // Close the connection after you are done.
        ghttp_set_header(request, http_hdr_Connection, "close");
        // Prepare the connection
        ghttp_prepare(request);
        // Process the request
        ghttp_process(request);
        // Write out the body. Note that the body of the request may not be null terminated so we have to be careful of the length. 
        fwrite(ghttp_get_body(request), ghttp_get_body_len(request), 1, stdout);
        // Destroy the request. This closes any file descriptors that may be open and will free any memory associated with the reque
st. 
        ghttp_request_destroy(request);
}

另一个网络上的实例：
netutil.h

    /*  
     * File:   netutil.h 
     * Author: Administrator 
     * 
     * Created on 2014年9月2日, 下午3:51 
     */  

    #ifndef NETUTIL_H  
    #define NETUTIL_H  

    #ifdef  __cplusplus  
    extern "C" {  
    #endif  
    int isFileExist(char * savePath);  
    int download(char *uri, char *savePath) ;  
    //result地址参数传递  
    int netGet(char* url, char* params, int timeout, char **result, int result_len) ;  
    int netPost(char* uri, char* params, int timeout, char **result, int result_len) ;  

    #ifdef  __cplusplus  
    }  
    #endif  

    #endif  /* NETUTIL_H */  

netutil.c

    #include "ghttp.h"  
    #include "http_hdrs.h"  
    #include <stdio.h>  
    #include <string.h>  
    #include <stdlib.h>  
    #include <io.h>  
    #include <unistd.h>  

    #define GET_ARRAY_LEN(array,len) {len = (sizeof(array) / sizeof(array[0]));}  

    int isFileExist(char * savePath) {  
        if (!access(savePath, F_OK)) {  
            return 1;  
        } else {  
            return 0;  
        }  
    }  
    //http://www.elesos.com/index.php?title=Libghttp库使用指南  

    int download(char *uri, char *savePath) {  
        ghttp_request *request = NULL;  
        ghttp_status status;  
        FILE * pFile;  
        char *buf;  
        int bytes_read;  
        int size;  
        if(!isFileExist(savePath))  
        {  
            printf("savePath not exist ");  

        }  
        pFile = fopen(savePath, "wb");  
        request = ghttp_request_new();  
        if (ghttp_set_uri(request, uri) == -1)  
            return -1;  
        if (ghttp_set_type(request, ghttp_type_get) == -1)//get  
            return -1;  
        ghttp_prepare(request);  
        status = ghttp_process(request);  
        if (status == ghttp_error)  
            return -1;  
        printf("Status code -> %d\n", ghttp_status_code(request));  
        buf = ghttp_get_body(request);  
        bytes_read = ghttp_get_body_len(request);  
        //size = strlen(buf); //size == bytes_read   
        //这里是错误的,当返回的数据为文本时,strlen的长度是正确,二进制数据如图片/apk时的长度是错误的。  
        size = bytes_read; //size != bytes_read  

        printf("buf :%s \n size :%d \n" , buf,size);  
        fwrite(buf, 1, size, pFile);  
        fclose(pFile);  
        ghttp_clean(request);  
        ghttp_request_destroy(request);  
        return 0;  
    }  
    //result地址参数传递  

    int netGet(char* url, char* params, int timeout, char **result, int result_len) {  
        ghttp_request *request = NULL;  
        request = ghttp_request_new();  

        if(params!=NULL&&strlen(params)>0)  
        {  
            char tmp[1024];  
            strcpy(tmp,url);  
            if(strchr(tmp, '?') == NULL)//url不存在  
            {     strcat(tmp,"?")  ;            
            }  
            strcat(tmp,params) ;    
            printf("%s\n",tmp);  
            ghttp_set_uri(request, tmp);        
        }else{  
             ghttp_set_uri(request, url);  
        }   
        ghttp_set_type(request, ghttp_type_get); //get方法  
        ghttp_set_header(request, http_hdr_Connection, "close");  
        char timeout_str[10];  
        sprintf(timeout_str, "%d", timeout);  
        ghttp_set_header(request, http_hdr_Timeout, timeout_str);    

        ghttp_prepare(request);  
        ghttp_process(request);  
        *result = ghttp_get_body(request);  
        result_len = ghttp_get_body_len(request);  
        ghttp_request_destroy(request);  
        return 0;  
    }  

    int netPost(char* uri, char* params, int timeout, char **result, int result_len) {  
        char szVal[1024];  
        ghttp_request *request = NULL;  
        ghttp_status status;  
        int len;  
        printf("%s\n", params); //test  
        request = ghttp_request_new();  
        if (ghttp_set_uri(request, uri) == -1)  
            return -1;  
        if (ghttp_set_type(request, ghttp_type_post) == -1) //post  
            return -1;  
        ghttp_set_header(request, http_hdr_Content_Type,"application/x-www-form-urlencoded");  

        char timeout_str[10];  
        sprintf(timeout_str, "%d", timeout);  
        ghttp_set_header(request, http_hdr_Timeout, timeout_str);  
        //ghttp_set_sync(request, ghttp_sync); //set sync  
        len = strlen(params);  
        ghttp_set_body(request, params, len); //  
        ghttp_prepare(request);  
        status = ghttp_process(request);  
        if (status == ghttp_error)  
            return -1;  
        *result = ghttp_get_body(request); //test  
        result_len=ghttp_get_body_len(request);  
        ghttp_clean(request);  
        return 0;  
    }  

main.c

    #include <stdlib.h>  

    #include "netutil.h"  

    int main(int argc, char *argv[]) {  
        char *result;  
        int len;  
        result=(char*)malloc(sizeof(char*)*8096);  
        memset(result, 0, sizeof(char*)*8096);  
        char param[2048]= "&lan=java&POSTDATA=15&f=ghttp";    
        netPost("http://127.0.0.1:8080/server/index.do",param, 5000, &result, len);  
        printf("%s\n%d\n", result, len);  
        netGet("http://127.0.0.1:8080/server/index.do?hehe=yy",param, 5000, &result, len);  
        printf("%s\n%d\n", result, len);  
        download("http://www.baidu.com/","test//fuck.html");  
        return 0;  
    }  

转自：http://www.phpjiayuan.com/109/270.html
转自:http://blog.csdn.net/earbao/article/details/39007549