is a type of interprocess communication
that allows communication between processes both locally and over a network
. The use of MailSlots is generally simpler than named pipes
, but they are more limited.
MailSlots function as a server-client interface. A server
can create a MailSlot, and a client
can write to it. Only the server can read the mailslot. A server-client interface could consist of two processes communicating locally or across a network. MailSlots do not operate over Wide Area Networks
such as the internet, though. Also, MailSlots offer no confirmation that a message has been received unless it is programmed into an application. MailSlots are generally a good choice when one process must broadcast a message to multiple processes, or if a fast and very easy solution is needed.
The most widely known implementation of the MailSlot is the Messenger service
that exists in Windows NT
-line of products, including Windows XP
. The Messenger service is essentially a MailSlot server that waits for a message to arrive. When a message arrives it is displayed in a popup onscreen. The
command is therefore a type of MailSlot client, because it writes to specified mailslots on a network.
A number of programs also use MailSlots to communicate. Generally these are amateur chat clients and other such programs. Commercial programs usually prefer pipes or sockets. Other MailSlots include:
- MAILSLOTMessngr - Microsoft
NET SEND Protocol
- MAILSLOTBrowse - Microsoft Browser Protocol
- MAILSLOTHydraLsServer - Microsoft Terminal Services Licensing
- MAILSLOTCheyenneDS - CA BrightStor Discovery Service