If the database contains a message with the given filename then, on
successful return (NOTMUCH_STATUS_SUCCESS) '*message' will be initialized to
a message object. The caller should call notmuch_message_destroy when done
with the message.
On any failure or when the message is not found, this function initializes
'*message' to NULL. This means, when NOTMUCH_STATUS_SUCCESS is returned, the
caller is supposed to check '*message' for NULL to find out whether the
message with the given filename is found.
Find a message with the given filename.
If the database contains a message with the given filename then, on successful return (NOTMUCH_STATUS_SUCCESS) '*message' will be initialized to a message object. The caller should call notmuch_message_destroy when done with the message.
On any failure or when the message is not found, this function initializes '*message' to NULL. This means, when NOTMUCH_STATUS_SUCCESS is returned, the caller is supposed to check '*message' for NULL to find out whether the message with the given filename is found.
Return value: