$ cat server.scm 
(use spiffy)

(root-path (current-directory))
(error-log (current-error-port))
(debug-log (current-error-port))


$ csi -s server
[Wed Nov 16 11:11:25 2011] "GET http://localhost:8080/foo.data HTTP/1.1" Error: (>)
bad argument type
#<procedure>

        Call history:

        g411412   
        close-input-port          
        raise     
        k465471   
        g512513516        
        g512513516        
        g469470   
        ##sys#signal      
        k668674   
        g569570577        
        g569570577        
        g571572578        
        g571572578        
        g672673   
        spiffy#handle-exception   
        with-output-to-string           <--


thread50: Closing off

$ csi -:a30 -s server.scm 
primordial: Incoming request from 127.0.0.1
[Wed Nov 16 11:30:40 2011] "GET http://localhost:8080/foo.data HTTP/1.1" Error: (>)
bad argument type
#<procedure>

        Call history:

        intarweb#request-method   
        eq?       
        spiffy#call-with-input-file*      
        call-with-input-file      
        call-with-current-continuation    
        with-exception-handler    
        ##sys#call-with-values    
        proc271   
        spiffy#current-response   
        intarweb#response-port    
        sendfile#sendfile         
        k273279   
        g277278   
        close-input-port          
        raise     
        k331337   
        g378379382        
        g378379382        
        g335336   
        memv      
        memv      
        ##sys#signal      
        k534540   
        g435436443        
        g435436443        
        g437438444        
        g437438444        
        g538539   
        spiffy#handle-exception   
        with-output-to-string           <--


thread50: Closing off