Task: Send email

C: #include <curl/curl.h>
#include <string.h>
#include <stdio.h>

#define from    "<sender@duniya.com>"
#define to      "<addressee@gmail.com>"
#define cc      "<info@example.org>"
 
static const char *payload_text[] = {
  "Date: Mon, 13 Jun 2018 11:30:00 +0100\r\n",
  "To: " to "\r\n",
  "From: " from " (Example User)\r\n",
  "Cc: " cc " (Another example User)\r\n",
  "Message-ID: <ecd7db36-10ab-437a-9g3a-e652b9458efd@"
  "rfcpedant.example.org>\r\n",
  "Subject: Sanding mail via C\r\n",
  "\r\n",
  "This mail is being sent by a C program.\r\n",
  "\r\n",
  "It connects to the GMail SMTP server, by far, the most popular mail program of all.\r\n",
  "Which is also probably written in C.\r\n",
  "To C or not to C..............\r\n",
  "That is the question.\r\n",
  NULL
};
 
struct upload_status {
  int lines_read;
};
 
static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp)
{
  struct upload_status *upload_ctx = (struct upload_status *)userp;
  const char *data;
 
  if((size == 0) || (nmemb == 0) || ((size*nmemb) < 1)) {
    return 0;
  }
 
  data = payload_text[upload_ctx->lines_read];
 
  if(data) {
    size_t len = strlen(data);
    memcpy(ptr, data, len);
    upload_ctx->lines_read++;
 
    return len;
  }
 
  return 0;
}
 
int main(void)
{
  CURL *curl;
  CURLcode res = CURLE_OK;
  struct curl_slist *recipients = NULL;
  struct upload_status upload_ctx;
 
  upload_ctx.lines_read = 0;
 
  curl = curl_easy_init();
  if(curl) {

    curl_easy_setopt(curl, CURLOPT_USERNAME, "user");
    curl_easy_setopt(curl, CURLOPT_PASSWORD, "secret");

    curl_easy_setopt(curl, CURLOPT_URL, "smtp:

    curl_easy_setopt(curl, CURLOPT_USE_SSL, (long)CURLUSESSL_ALL);
 
    curl_easy_setopt(curl, CURLOPT_CAINFO, "/path/to/certificate.pem");

    curl_easy_setopt(curl, CURLOPT_MAIL_FROM, from);

    recipients = curl_slist_append(recipients, to);
    recipients = curl_slist_append(recipients, cc);
    curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);

    curl_easy_setopt(curl, CURLOPT_READFUNCTION, payload_source);
    curl_easy_setopt(curl, CURLOPT_READDATA, &upload_ctx);
    curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);

    curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);

    res = curl_easy_perform(curl);

    if(res != CURLE_OK)
      fprintf(stderr, "curl_easy_perform() failed: %s\n",curl_easy_strerror(res));

    curl_slist_free_all(recipients);

    curl_easy_cleanup(curl);
  }
 
  return (int)res;
}











Ada: with AWS.SMTP, AWS.SMTP.Client, AWS.SMTP.Authentication.Plain;
with Ada.Text_IO;
use  Ada, AWS;

procedure Sendmail is
   Status : SMTP.Status;
   Auth : aliased constant SMTP.Authentication.Plain.Credential :=
      SMTP.Authentication.Plain.Initialize ("id", "password");
   Isp : SMTP.Receiver;
begin
   Isp :=
      SMTP.Client.Initialize
        ("smtp.mail.com",
         Port       => 5025,
         Credential => Auth'Unchecked_Access);
   SMTP.Client.Send
     (Isp,
      From    => SMTP.E_Mail ("Me", "me@some.org"),
      To      => SMTP.E_Mail ("You", "you@any.org"),
      Subject => "subject",
      Message => "Here is the text",
      Status  => Status);
   if not SMTP.Is_Ok (Status) then
      Text_IO.Put_Line
        ("Can't send message :" & SMTP.Status_Message (Status));
   end if;
end Sendmail;