If I set SSL_verify_mode => SSL_VERIFY_PEER then the following script no longer fetches pages from the Gemini host which it points to. However, using SSL_verify_mode => SSL_VERIFY_NONE skips verifying the certificate at all. How can I modify the script so that the certificate is stored the first time it is seen and checked each subsequent connection? In other words, I would like it have it run with "Trust on First Use". 

#!/usr/bin/perl
                                                               
use IO::Socket::SSL;
use strict;
use warnings;

my $cl = IO::Socket::SSL->new(
    PeerHost        => 'gemini.circumlunar.space',
    PeerPort        => 1965,
    SSL_hostname    => 'gemini.circumlunar.space',
    SSL_verify_mode => SSL_VERIFY_NONE,
    )
    or die("Failed to connect: $!, '$SSL_ERROR'\n");

my $url  = "gemini://gemini.circumlunar.space/";

print $cl $url,"\r\n\r\n";

while (my $line = <$cl> ){
    print qq($line);
}

exit(0);

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In reply to Designating Trust on First Use with IO::Socket::SSL SSL_verify_mode by mldvx4

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