请帮我写一个C++的程序，实现邮件方式发送图片

抱歉，我是一名语言模型，无法编写和执行代码。但我可以提供一些思路和建议：

要发送图片，可以使用邮件协议中的附件功能。具体步骤如下：

1. 打开要发送的图片文件，读取图片内容；
2. 将图片内容编码为base64格式，以便在邮件中传输；
3. 使用SMTP协议发送邮件，设置邮件主题、发件人、收件人、内容类型等参数；
4. 将图片内容作为附件添加到邮件中，设置附件名称和类型；
5. 发送邮件。

以下是一个示例代码，仅供参考：

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

#define SMTP_SERVER "smtp.gmail.com"
#define SMTP_PORT 587
#define SMTP_USER "your_username@gmail.com"
#define SMTP_PASS "your_password"

#define FROM_ADDR "your_username@gmail.com"
#define TO_ADDR "recipient@example.com"
#define SUBJECT "Test Email with Attachment"

#define IMG_FILE "test.jpg"
#define IMG_NAME "test.jpg"
#define IMG_TYPE "image/jpeg"

int main()
{
    CURL *curl;
    CURLcode res;
    struct curl_slist *recipients = NULL;
    struct curl_slist *headers = NULL;
    char payload[4096];
    char encoded_img[4096];
    FILE *fp;
    long img_size;
    size_t result;

    // read image file
    fp = fopen(IMG_FILE, "rb");
    if (fp == NULL) {
        printf("Failed to open file!\n");
        return 1;
    }
    fseek(fp, 0, SEEK_END);
    img_size = ftell(fp);
    rewind(fp);
    char *img_data = (char *) malloc(img_size + 1);
    result = fread(img_data, 1, img_size, fp);
    if (result != img_size) {
        printf("Failed to read file!\n");
        fclose(fp);
        return 1;
    }
    fclose(fp);

    // encode image in base64
    CURL *enc = curl_easy_init();
    CURLcode enc_res;
    enc_res = curl_easy_escape(enc, img_data, img_size);
    if (enc_res != CURLE_OK) {
        printf("Failed to encode image!\n");
        return 1;
    }
    strcpy(encoded_img, enc->out_buf);
    curl_easy_cleanup(enc);

    // create email payload
    sprintf(payload, "From: %s\r\n", FROM_ADDR);
    sprintf(payload + strlen(payload), "To: %s\r\n", TO_ADDR);
    sprintf(payload + strlen(payload), "Subject: %s\r\n", SUBJECT);
    sprintf(payload + strlen(payload), "MIME-Version: 1.0\r\n");
    sprintf(payload + strlen(payload), "Content-Type: multipart/mixed; boundary=boundary1\r\n\r\n");
    sprintf(payload + strlen(payload), "--boundary1\r\n");
    sprintf(payload + strlen(payload), "Content-Type: text/plain\r\n\r\n");
    sprintf(payload + strlen(payload), "This is a test email with attachment.\r\n\r\n");
    sprintf(payload + strlen(payload), "--boundary1\r\n");
    sprintf(payload + strlen(payload), "Content-Type: %s; name=%s\r\n", IMG_TYPE, IMG_NAME);
    sprintf(payload + strlen(payload), "Content-Disposition: attachment; filename=%s\r\n", IMG_NAME);
    sprintf(payload + strlen(payload), "Content-Transfer-Encoding: base64\r\n\r\n");
    sprintf(payload + strlen(payload), "%s\r\n\r\n", encoded_img);
    sprintf(payload + strlen(payload), "--boundary1--\r\n");

    // initialize curl
    curl = curl_easy_init();
    if (curl) {
        // set smtp server and port
        curl_easy_setopt(curl, CURLOPT_URL, SMTP_SERVER);
        curl_easy_setopt(curl, CURLOPT_PORT, SMTP_PORT);

        // set user authentication
        curl_easy_setopt(curl, CURLOPT_USERNAME, SMTP_USER);
        curl_easy_setopt(curl, CURLOPT_PASSWORD, SMTP_PASS);

        // set email parameters
        curl_easy_setopt(curl, CURLOPT_MAIL_FROM, FROM_ADDR);
        recipients = curl_slist_append(recipients, TO_ADDR);
        curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);
        headers = curl_slist_append(headers, "Content-Type: text/plain");
        curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);

        // set email payload
        curl_easy_setopt(curl, CURLOPT_READFUNCTION, NULL);
        curl_easy_setopt(curl, CURLOPT_READDATA, NULL);
        curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
        curl_easy_setopt(curl, CURLOPT_READFUNCTION, NULL);
        curl_easy_setopt(curl, CURLOPT_READDATA, payload);
        curl_easy_setopt(curl, CURLOPT_INFILESIZE, (long) strlen(payload));

        // send email
        res = curl_easy_perform(curl);
        if (res != CURLE_OK) {
            printf("Failed to send email: %s\n", curl_easy_strerror(res));
        }

        // cleanup
        curl_slist_free_all(recipients);
        curl_slist_free_all(headers);
        curl_easy_cleanup(curl);
    }

    return 0;
}

需要注意的是，该示例代码使用了libcurl库来发送SMTP邮件，并以Gmail为例。如果使用其他邮箱服务，请根据实际情况修改SMTP服务器地址、端口、用户名、密码等参数。同时，也需要确认libcurl库是否已经正确安装并链接。