dynamic(3) User Contributed Perl Documentation dynamic(3)

NAME
       PerlIO::via::dynamic - dynamic PerlIO layers

SYNOPSIS
        open $fh, $fname;
        $p = PerlIO::via::dynamic->new
         (translate =>
           sub { $[1] =~ s/\$Filename[:\w\s\-\.\/\\]*\$/\$Filename: $fname\$/e},
          untranslate =>
           sub { $[1] =~ s/\$Filename[:\w\s\-\.\/\\]*\$/\$Filename\$/});
        $p->via ($fh);
        binmode $fh, $p->via; # deprecated

DESCRIPTION
       "PerlIO::via::dynamic" is used for creating dynamic PerlIO layers. It
       is useful when the behavior or the layer depends on variables. You
       should not use this module as via layer directly (ie :via(dynamic)).

       Use the constructor to create new layers, with two arguments: translate
       and untranslate. Then use "$p-"via ($fh)> to wrap the handle.  Once
       <$fh> is destroyed, the temporary namespace for the IO layer will be
       removed.

       Note that PerlIO::via::dynamic uses the scalar fields to reference to
       the object representing the dynamic namespace.

OOPPTTIIOONNSS
       translate
           A function that translate buffer upon write.

       untranslate
           A function that translate buffer upon read.

       useread
           Use "READ" instead of "FILL" for the layer.  Useful when caller
           expect exact amount of data from read, and the "untranslate"
           function might return different length.

           By default "PerlIO::via::dynamic" creates line-based layer to make
           "translate" implementation easier.

AUTHORS
       Chia-liang Kao 

COPYRIGHT
       Copyright 2004 by Chia-liang Kao .

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

       See 



perl v5.8.8                       2006-03-06                        dynamic(3)