How can I using strings that contains "$"

HI

 

 

maybe a basic question about TCL. I have a special application that insert http header like below:

 

 

GET /snoop HTTP/1.1

 

Host: 122.138.13.143

 

Connection: Keep-Alive

 

$WSRA: 122.135.31.9

 

 

where the $WSRA is the http header name. but when I want using the header as:

 

 

set a [HTTP::header $WSRA]

 

 

or

 

 

set a [HTTP::header $$WSRA]

 

 

will returen an error that can't find variable WSRA.

 

 

How can I do?

 

 

TIA