Thanks for the responses.

In a CGI script, you usually don't need to care about ending the headers. Just use the $cgi->header(...) method correctly.

In my case, I can't do that. I'm trying to read some simple json data in the body of a post request, but $cgi->{POSTDATA} gives me inconsistent results depending on my server. With an apache server, POSTDATA successfully contains the json. However, I tried my perl script on another server, and POSTDATA returns undef. To solve that issue, I'm reading from STDIN directly. I looked at the source code for CGI.pm, and I don't understand why CGI.pm fails to read the json while executing on my non-apache server, because I can get the json when I read from STDIN directly doing this:

(The cgi spec requires that a script not try to read more than Content-Length from STDIN.)

#!/usr/bin/env perl

use strict;
use warnings;
use 5.020;
use autodie;
use Data::Dumper;
use JSON;

if (my $content_len = $ENV{CONTENT_LENGTH}) {

    read(STDIN, my $json, $content_len);   #<===HERE ************
    my $href = decode_json($json);
    my $a = $href->{a};
    my $b = $href->{b};

    print 'Content-type: text/html';
    print "\r\n\r\n";
    print "<div>a=$a</div>";
    print "<div>b=$b</div>";
} 
else {
    my $error = "Could not read json: No Content-Length header in requ
+est.";
    print 'Content-type: text/html';
    print "\r\n\r\n";
    print "<div>$error</div>";
}

[download]
And, once I read from STDIN directly, then none of perl's CGI functionality works.

In reply to Re: CGI: newlines, write exactly "\r\n" to end the headers, then turn off binmode by 7stud
in thread CGI: newlines, write exactly "\r\n" to end the headers, then turn off binmode by 7stud

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