use strict;
use warnings;

use CGI;

my $cgi = CGI->new();

sub handle_error {
    print $cgi->header(
        -status => 500,
        -type   => 'text/html',
    );
    print ...;
    exit(0);
}

open(my $fh, '<', 'foo.csv')
    or handle error(...);

print $cgi->header(
    # application/octet-stream might work better
    -type       => 'text/csv',
    -attachment => 'foo.csv',
);

print while <$fh>;
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Of course, you can base the name of the CSV on a CGI parameter or on a session field. Or you can generate it on the fly instead of reading it form disk.

Thanks! Your idea made this even more compact:

    my $cgi = CGI->new();
    my $s = "Hi, Mom!\n";
    print $cgi->header(-type => 'text/csv', -attachment => 'filename.c
+sv', -Content-length => length($s));
    print $s;
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Is it possible to generate the standard file-open dialog such that the filename can be changed?

To pick the name of the file to which to save? Your browser should do that already.

If you mean that you want the browser to prompt the user where to download your CSV file, that's a matter of sending the proper HTTP headers. In your case, you need to send the appropriate Content-Disposition header:

print "Content-Disposition: attachment; filename=test.csv\r\n\r\n";
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Thanks! The following appears to work:

    my $s = "Hi, Mom!\n";
#    print "Content-disposition: inline; filename=docket.csv\n";
    print "Content-disposition: attachment; filename=docket.csv\n";
    print "Content-length: " . length($s) . "\n";
    print "Content-type: application/octet-stream\n\n";
    print $s;
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Specifying inline or attachment appears to work in the same manner.

Is there a way to display the standard file-open dialog such that the user can rename the file as desired?

Thanks, again!

Content-type:text/csv\n\n
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