Sample code for 30+ languages & platforms
Unicode C

Mark IMAP Email as Read/Unread (Seen/Unseen)

Demonstrates how to mark emails as read or unread.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkImapW.h>
#include <C_CkEmailW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkImapW imap;
    int numMsgs;
    HCkEmailW email;
    int i;
    BOOL bIsUid;

    success = FALSE;

    //  This example assumes the Chilkat API to have been previously unlocked.
    //  See Global Unlock Sample for sample code.

    imap = CkImapW_Create();

    //  Connect to an IMAP server.
    //  Use TLS
    CkImapW_putSsl(imap,TRUE);
    CkImapW_putPort(imap,993);
    success = CkImapW_Connect(imap,L"imap.example.com");
    if (success == FALSE) {
        wprintf(L"%s\n",CkImapW_lastErrorText(imap));
        CkImapW_Dispose(imap);
        return;
    }

    //  Login
    success = CkImapW_Login(imap,L"myLogin",L"myPassword");
    if (success == FALSE) {
        wprintf(L"%s\n",CkImapW_lastErrorText(imap));
        CkImapW_Dispose(imap);
        return;
    }

    //  Select an IMAP mailbox
    success = CkImapW_SelectMailbox(imap,L"Inbox");
    if (success == FALSE) {
        wprintf(L"%s\n",CkImapW_lastErrorText(imap));
        CkImapW_Dispose(imap);
        return;
    }

    //  Set PeekMode so that downloaded messages are not
    //  automatically marked as seen.
    CkImapW_putPeekMode(imap,TRUE);

    //  The NumMessages property contains the number of messages 
    //  in the currently selected mailbox.
    numMsgs = CkImapW_getNumMessages(imap);
    if (numMsgs == 0) {
        CkImapW_Dispose(imap);
        return;
    }

    email = CkEmailW_Create();

    for (i = 1; i <= numMsgs; i++) {
        //  Download each email by sequence number (not UID)
        success = CkImapW_FetchEmail(imap,FALSE,i,FALSE,email);
        if (success == FALSE) {
            wprintf(L"%s\n",CkImapW_lastErrorText(imap));
            CkImapW_Dispose(imap);
            CkEmailW_Dispose(email);
            return;
        }

        //  If desired, mark the email as SEEN.  There are two
        //  ways to do it:

        //  1) Set the flag directly by using the sequence number
        //  Indicate that we are passing a sequence number and
        //  not a UID:
        bIsUid = FALSE;
        //  Set the SEEN flag = 1 to mark the email as SEEN,
        //  or set it to 0 to mark it as not-seen.
        success = CkImapW_SetFlag(imap,i,bIsUid,L"SEEN",1);
        if (success == FALSE) {
            wprintf(L"%s\n",CkImapW_lastErrorText(imap));
            CkImapW_Dispose(imap);
            CkEmailW_Dispose(email);
            return;
        }

        //  2) Alternatively, we can use the email object.
        //  When an email is downloaded from the IMAP server
        //  Chilkat will add a "ckx-imap-uid" header to the email.
        //  This makes it possible to know the UID associated with
        //  the email.  (This is not the sequence number, which may change
        //  from session to session, but the UID which does not change.
        //  The SetMailFlag method is identical to SetFlag, except
        //  it gets the UID from the ckx-imap-uid header.
        //  For example:
        success = CkImapW_SetMailFlag(imap,email,L"SEEN",1);
        if (success == FALSE) {
            wprintf(L"%s\n",CkImapW_lastErrorText(imap));
            CkImapW_Dispose(imap);
            CkEmailW_Dispose(email);
            return;
        }

    }

    //  Disconnect from the IMAP server.
    success = CkImapW_Disconnect(imap);


    CkImapW_Dispose(imap);
    CkEmailW_Dispose(email);

    }