perl - CGI-ExtDirect-2.02 can't call method "result" on an undefined value -

i working on converting interface of perl web application ext , intended use cgi-extdirect-2.02 library.

i encountered problem though, which, after many hours of struggling, still remains unresolved.

in simplest use case problem is: when adding following lines action method, example, demo/testaction/getgrid, error occurs in router.pm. same error appears both when executed under apache or using included library p5httpd.pl server.

when remove while(<file>) loop, error goes away , else works fine.

system configuration is:

sunos 5.10, apache 2, perl 5.12.1. 

lines add:

open(file, "</tmp/test.txt") or die("can't open file: $!"); while (<file>) {     ; } close(file); 

error:

5571 17:58:08 server started on port 5000. 5571 17:58:08 5571 17:58:08 point browser @ http://localhost:5000 5571 17:58:11 <- localhost: /direct-grid.html http/1.1 5571 17:58:11 -> 200 ok /direct-grid.html: 803 bytes sent text/html 5571 17:58:11 <- localhost: /example.css http/1.1 5571 17:58:11 -> 200 ok /example.css: 1501 bytes sent text/css 5571 17:58:11 <- localhost: /direct-grid.js http/1.1 5571 17:58:11 -> 200 ok /direct-grid.js: 1599 bytes sent application/x-javascript 5571 17:58:11 <- localhost: /cgi-bin/api.cgi http/1.1 5571 17:58:11 -> exec'ing api.cgi 5571 17:58:13 <- localhost: post /cgi-bin/router.cgi http/1.1 5571 17:58:13 <- content-length: 119, type: application/json; charset=utf-8 5571 17:58:13 -> exec'ing router.cgi  can't call method "result" on undefined value @ /usr/perl5/site_perl/5.12.1/rpc/extdirect/router.pm line 136.  5571 17:58:13 -> 500 internal server error premature end of script headers. <br> status: 65280<br>have @ server log stderr output of /cgi-bin/router.cgi 

if loop has nothing problem, there problem file superglobal conflicting something. try changing like

open $if, "<", "/tmp/test.txt"; while(<$if>) {     # whatever } close $if;