Here is an example from the docs for IO::Scalar:

    ### Open a handle on a string, read it line-by-line, then close it
+:
    $SH = new IO::Scalar \$data;
    while (defined($_ = $SH->getline)) {
        print "Got line: $_";
    }
    $SH->close;
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I know you were looking for an approach that uses or acts like a filehandle, but here is something that uses split instead:

use warnings;
use strict;

my $string = "This is some text\nto be processed as\na file";

# use a zero-width positive look-behind assertion to split
# the string on whatever is used as the input record
# separator ($/) without consuming it
foreach my $line ( split( m[(?<=$/)], $string ) )
{
    print $line;
}

# or, if you prefer the one-liner look
print for split ( m[(?<=$/)], $string );
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Update: Added the alternate form of the for/split loop.