[Home](./index.md) > [sip.js](./sip.js.md) > [IncomingMessage](./sip.js.incomingmessage.md) > [s](./sip.js.incomingmessage.s.md) ## IncomingMessage.s() method Message Header attribute selector. Alias of parseHeader. Signature: ```typescript s(name: string, idx?: number): any | undefined; ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | name | string | header name | | idx | number | header index | Returns: `any | undefined` Parsed header object, undefined if the header is not present or in case of a parsing error. ## Example message.s('via',3).port