The header
The header section of a mail rule determines which header field in the envelope a rule should be run on. For example, To, From, Subject, Date, Return-Path, X-headers, and so on. This is what the different characters in the Header mean:
• ^ apply this rule before any headers are processed
This character is useful for initializing script variables.
• * apply this rule on every RFC-2822 header
This character is useful for scanning all headers for a particular value.
• " (empty)
Apply this rule after the last header has been processed.
This character is useful for acting on data tallied by other rules.
• @ apply this rule at the end of each set of attachment headers.
• < apply this rule for each <A and <IMG link in the HTML message as it is parsed.
• > apply this rule when the end of the message body is reached.
• . apply this rule when the end of the message is reached.
This character is useful for acting on data tallied by other rules.
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