Sieve is a language for filtering email messages, it’s defined in the Internet standard, also it’s called as Sieve: An Email Filtering Language. It provides a simple, human-readable syntax for specifying rules that determine what actions to take on incoming email messages. These actions can include filing messages into different folders, forwarding messages to other addresses, discarding messages, and more.
Sieve is typically used in email servers and clients, and it can be used to implement server-side and client-side email filtering. It allows users to create their own rules for filtering email, without requiring access to the server’s configuration or the need for complex server-side scripts.
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