I'm using the following subroutine to send a binary (PDF) file back to the client's browser. 

# IMPORTANT MODULES FOR THIS CODE...
use CGI qw(-utf8); 
use File::Spec::Functions qw( catfile );

sub send_file {
    my ($cgi, $dir, $file) = @_;

    # $dir = '/var/www/download/';
    # $file = 'MyLaTeXDocument.pdf';

    my $path = catfile($dir, $file);
        
    open my $fh, '<:raw', $path or die "Cannot open '$path': $!\n";

    $cgi->charset(''); #REMOVES PRIOR UTF-8 SETTING, AS THIS IS BINARY
+ FILE
    print $cgi->header(
        -type => 'application/octet-stream',
        -attachment => $file,
    );

    binmode STDOUT, ':raw';
    print while <$fh>;    
    close $fh or die "Cannot close '$path': $!";

    return;
}

[download]

The browser console sees a string of characters returning in the response, but no download dialogue is opened.

Response headers

Connection
    Keep-Alive
Content-Disposition
    attachment; filename="MyLaTeXDocument.pdf"
Content-Type
    application/octet-stream
Date
    Fri, 22 Sep 2023 11:13:27 GMT
Keep-Alive
    timeout=5, max=100
Server
    Apache/2.4.52 (Ubuntu)
Transfer-Encoding
    chunked

[download]

Response Payload

JVBERi0xLjUKJeTw7fg... [truncated...too lazy to type more]

[download]
Why won't the browser just open the "Save as..." dialogue? As it stands, the browser appears to do nothing, silently dropping this activity in background. What is lacking in this code?

Blessings,

~Polyglot~

In reply to Perl output is not inducing file download as expected by Polyglot

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