Hack to have zeta dump IMAP I/O to console

000.md

Apply the patch, then run the IMAP test on CLI:

cv api4 MailSettings.testConnection +w id=3

hack-dump-io.diff

--- vendor/zetacomponents/mail/src/transports/transport_connection.php.orig	2020-11-06 21:22:43.000000000 -0800
+++ vendor/zetacomponents/mail/src/transports/transport_connection.php.new	2020-11-06 21:22:07.000000000 -0800
@@ -194,6 +194,7 @@
     {
         if ( is_resource( $this->connection ) )
         {
+            fwrite(STDERR, '>> ' . $data . self::CRLF);
             if ( fwrite( $this->connection, $data . self::CRLF,
                         strlen( $data ) + strlen( self::CRLF  ) ) === false )
             {
@@ -235,6 +236,7 @@

                 $data .= $line;
             }
+            fwrite(STDERR, '<< ' . $data . self::CRLF);

             if ( $trim == false )
             {