For each message to be sent with PMDF_send, an item list describing the message to be sent must first be built. The entries in this item list specify the message's "From:" and "To:" addresses as well as input sources for the content of the message. The basic steps in sending a message with callable send are:

1. Build the item list to pass to PMDF_send:
   1. specify any special processing options (e.g., PMDF_BLANK, PMDF_NOIGNORE_ERRORS, etc.);
   2. specify the message's envelope "From:" address with the PMDF_USER item;
   3. specify the message's "To:", "Cc:", and "Bcc:" addresses with the PMDF_TO, PMDF_CC, and PMDF_BCC items;
   4. an initial message header can be specified through an input source which supplies each of the initial message header lines ( PMDF_HDR_FILE, PMDF_HDR_PROC), or the content of individual message header lines can be specified with individual item codes ( PMDF_SUBJECT, PMDF_REPLY_TO, PMDF_ORGANIZATION, etc.);
   5. specify the input sources for the message body with the PMDF_MSG_FILE or PMDF_MSG_PROC items; and then
   6. terminate the item list with PMDF_END_LIST.
2. Pass the item list to PMDF_send.
3. Check the return status from PMDF_send.