有关 libcurl 例子

#include <stdio.h>
#include <curl/curl.h>

#include <string>
using std::string;

struct memory
{
    char *response;
    size_t size;

//    memory()
//    {
//        response = ( char * )calloc( 1, 1 );
//        size = 0;
//    }
//
//    ~memory()
//    {
//        free( response );
//        response = NULL;
//        size = 0;
//    }
};

size_t cb( void *data, size_t size, size_t nmemb, void *userp )
{
    size_t realsize = size * nmemb;
    struct memory *mem = ( struct memory * )userp;

    char *ptr = ( char* )realloc( mem->response, mem->size + realsize + 1 );
    if( ptr == NULL )
        return 0;  /* out of memory! */

    mem->response = ptr;
    memcpy( &( mem->response[mem->size] ), data, realsize );
    mem->size += realsize;
    mem->response[mem->size] = 0;

    return realsize;
}


//获取
size_t writefile_callback( char *buffer, size_t size, size_t nmemb, void *userdata )
{
    return fwrite( buffer, size, nmemb, ( FILE * )userdata );
}

size_t writemem_callback( char *buffer, size_t size, size_t nmemb, string &userdata )
{
    size_t rsize = size * nmemb;
    userdata.append( buffer, rsize );
    return rsize;
}

size_t readfile_callback( char *buffer, size_t size, size_t nmemb, void *userdata )
{
    return fread( buffer, size, nmemb, ( FILE * )userdata );
}




CURL *curl;
CURLcode res;
curl_global_init( CURL_GLOBAL_ALL );
curl = curl_easy_init();

if( curl )
{

    curl_easy_setopt( curl, CURLOPT_URL, "https://example.com" );


// https://
    curl_easy_setopt ( curl, CURLOPT_SSL_VERIFYHOST, 0L ); // set peer and host verify false
    curl_easy_setopt ( curl, CURLOPT_SSL_VERIFYPEER, 0L ); // if want to use https



    curl_easy_setopt( curl, CURLOPT_COOKIEFILE, "./cookies.txt" ); /* read cookie */
    curl_easy_setopt( curl, CURLOPT_COOKIEJAR, "./cookies.txt" ); /* write cookie */

    curl_easy_setopt( curl, CURLOPT_COOKIE, "tool=curl; fun=yes;" );

    curl_easy_setopt( curl, CURLOPT_PROXY, "127.0.0.1:8888" ); //代理


    curl_easy_setopt( pCurl, CURLOPT_TIMEOUT, 3L ); //请求超时时长
    curl_easy_setopt( pCurl, CURLOPT_CONNECTTIMEOUT, 10L ); //连接超时时长


    curl_easy_setopt( curl, CURLOPT_HEADER, 1L ); // 头部和主体一起获取
    curl_easy_setopt( curl, CURLOPT_NOBODY, 1L );

//             disable progress meter, set to 0L to enable it
    curl_easy_setopt( curl, CURLOPT_NOPROGRESS, 0L );
//             Switch on full protocol/debug output
    curl_easy_setopt( curl, CURLOPT_VERBOSE, 1L );
//             example.com is redirected, so we tell libcurl to follow redirection
    curl_easy_setopt( curl, CURLOPT_FOLLOWLOCATION, 0L );

    struct memory chunk = {0};
    curl_easy_setopt ( curl, CURLOPT_WRITEFUNCTION, cb );
    curl_easy_setopt ( curl, CURLOPT_WRITEDATA, ( void * ) &chunk );
    free ( chunk.response );


    string rdata;
    curl_easy_setopt( curl, CURLOPT_WRITEFUNCTION, writemem_callback );
    curl_easy_setopt( curl, CURLOPT_WRITEDATA, &rdata );


    FILE* fp = fopen( filename, "wb" );
    curl_easy_setopt( curl, CURLOPT_WRITEFUNCTION, writefile_callback() );
    curl_easy_setopt( curl, CURLOPT_WRITEDATA, fp );



    FILE* fp = fopen( filename, "rb" );
    fseek( fp, 0, SEEK_END );
    long len = ftell( fp );
    fseek( fp, 0, SEEK_SET );
    // fclose( fp );

    curl_easy_setopt( curl, CURLOPT_READFUNCTION, readfile_callback );
    curl_easy_setopt( curl, CURLOPT_READDATA, fp );
    curl_easy_setopt( curl, CURLOPT_INFILESIZE, len );

    curl_easy_setopt( curl, CURLOPT_UPLOAD, 1L );

    curl_easy_setopt ( curl, CURLOPT_POST, 1L );
    curl_easy_setopt( curl, CURLOPT_POSTFIELDS, postdata );
    curl_easy_setopt( curl, CURLOPT_POSTFIELDSIZE, postdatalen );

    struct curl_slist *list = NULL;
    list = curl_slist_append( list, "origin: https://example.com" );
    list = curl_slist_append( list, "Content-Type: multipart/form-data" );
    list = curl_slist_append( list, "Expect:" );
    curl_easy_setopt( curl, CURLOPT_HTTPHEADER, list );

    fclose( fp );


#ifndef DISABLE_SSH_AGENT
    curl_easy_setopt( curl, CURLOPT_URL, "sftp://user:pass@example.com/path/filename" );
//   curl_easy_setopt( curl, CURLOPT_URL, "sftp://example.com/path/filename" );
//   curl_easy_setopt( curl, CURLOPT_USERPWD, "USER:PWD" );

    /* We activate ssh agent. For this to work you need
       to have ssh-agent running (type set | grep SSH_AGENT to check) or
       pageant on Windows (there is an icon in systray if so) */
    // curl_easy_setopt(curl, CURLOPT_SSH_AUTH_TYPES, CURLSSH_AUTH_AGENT);
    curl_easy_setopt( curl, CURLOPT_SSH_AUTH_TYPES, CURLSSH_AUTH_PASSWORD );
    //      curl_easy_setopt ( curl, CURLOPT_SSH_AUTH_TYPES, CURLSSH_AUTH_DEFAULT );
#endif


    if( res == CURLE_OK )
    {
        long response_code = 0;
        curl_easy_getinfo( curl, CURLINFO_RESPONSE_CODE, &response_code );
        if( response_code == 200 )
        {

        }
    }
    else
        fprintf( stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror( res ) );

    curl_slist_free_all( list );
    curl_easy_cleanup( curl );

}

curl_global_cleanup();

标签：setopt,libcurl,有关,例子,easy,curl,response,CURLOPT,size
来源： https://blog.csdn.net/wzxiaodu/article/details/122867705