mail::ACCOUNT::getMessageEnvelope — Return message header envelope
        
        
        #include <libmail/sync.H>
        
        #include <libmail/envelope.H>
        
        mail::ACCOUNT *mail;
| bool
            ok=mail->getMessageEnvelope( | const std::vector<size_t> &msgList, | 
| std::vector<mail::xenvelope> &envelopes ); | 
        std::string errmsg=mail->getErrmsg();
| mail::xenvelope myEnvelope=mail->getMessageEnvelope( | size_t messageNum ); | 
msgList specifies
      a list of messages. Messages are numbered starting with
      message #0 and up to one less than mail::ACCOUNT::getFolderIndexSize(3x)
      (when mail::account::getFolderIndexSize returns
      6, the messages are numbered 0 through 5). Only the messages
      that appear in msgList are processed by this
      request. When a message is removed from the folder, by
      mail::ACCOUNT::updateFolderIndexInfo(3x),
      the following messages are renumbered accordingly.
Most mail servers allow multiple applications to open the same folder. Therefore, changes to the folder's contents can occur at any time. Before making this request, the application should use mail::ACCOUNT::checkNewMail(3x) to verify that no unexpected changes have been made to the folder's contents.
This function reads the message envelope header
      information of each message specified by msgList. This function
      initializes the envelopes array to the same
      size as msgList, with
      each array member containing the envelope header information
      for the corresponding message in msgList.
The mail::xenvelope structure is a subclass of mail::envelope(3x), with two additional fields:
When this message was received by the mail server
              (or 0 if the time cannot
              be determined).
The approximate size of the message, in bytes. This size should be considered as an estimated only, and the actual size may be slightly higher or lower.
This method returns true if
      it succeeds, or false if it
      fails. If the method fails, use mail::ACCOUNT::getErrmsg() to
      read a brief description of the error.
The second version of mail::ACCOUNT::getMessageEnvelope returns
      the envelope information of a single message, ignoring any
      error condition (a failure results in the returned
      mail::xenvelope object being
      completely empty).