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8.39. CGI::Push

Provides an interface to do server push operations, letting you rewrite pages with content that changes regularly. A server push operation automatically sends updates to a page on a push-capable browser. CGI::Push exports the function do_push to implement page redraws. This method can be used on a CGI::Push object or on its own: 

$q = new CGI::Push;
$q->do_push(-next_page => \&sub);

or:

do_push (-next_page => \&sub);

do_push requires one argument: a reference to a subroutine that will draw the next page. You may optionally specify a subroutine that draws the last page and the interval between page updates. Additional parameters to do_push are those that can be used with a CGI::headers object.

do_push
do_push (params)

Implements a server push operation, which updates a page at specific intervals. Parameters are:

-delay => n
Specifies the number of seconds, n, to wait before the next call to the page-drawing subroutine.

-last_page => \&sublast
Runs the subroutine sublast to draw the last page update of a server push operation. The -last_page routine is invoked when the -next_page routine returns false. A reference to a subroutine glob should be provided for this parameter, but the name of the subroutine is also acceptable.

-next_page => \&sub
sub is the name of the subroutine responsible for redrawing the page and counting the number of iterations (if you want repeated updating). The do_push routine ends when sub returns false (or when the -last_page subroutine is invoked). A reference to a subroutine glob should be provided for this parameter, but the name of the subroutine is also acceptable.

-type = string
Specifies the content type of the pushed data. The default value is text/html.

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