Finisar Surveyor manual Filter Structure

Capture and Display Filters 7

Multi-State and Multi-Statement Filters

Filter Structure

The capture or display filter consists of states, each with a unique label so it can be referenced. Each state contains an IF statement, an ELSE statement, and optional ELSE IF statements. Each IF or ELSE IF statement is comprised of a condition to match against packets and the actions to implement if the condition matches. The ELSE statement is a set of actions to take when the other statements are false. The actions result in the subset of data that is captured or displayed by Surveyor. The statements and labels have an order, structure, and syntax. You always start and stay in State0 until an action takes you to a different state.

Capture and display filters have the following structure:

ROOT statement (The root statement for capture filters con- tains settings for global variables. The root statement for display filters contains no variables.)

STATE0 identifier	(Label for GoTo Action to Change the Fil-
ter	Operation -- Initial Starting Point)

IF statement (Specify conditions and actions)

ELSE IF statement (optional - same structure as IF statement) other ELSE IF statements

ELSE statement (if no conditions satisfied, take these actions)

STATE1 identifier (Label for GoTo Action to Change the Filter Operation)

IF statement (Specify conditions and actions)

ELSE IF statement (optional - same structure as IF statement) other ELSE IF statements

ELSE statement (if no conditions satisfied, take these actions)

. ...

. ...

. ..

STATE3 identifier (Label for GoTo Action to Change the Filter Operation)

IF statement (Specify conditions and actions)

ELSE IF statement (optional - same structure as IF statement) other ELSE IF statements

ELSE statement (if no conditions satisfied, take these actions)

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