First of all you are trying to connect into an SSL server but your /sockopen does not has the correct port and did not had -e parameter (/help /sockopen)

Second you dont have to put the HOLE url link into the POST.

And please next code post please use "[ code ] [ /code ]" forum quotes because the copy paste (e.g: the link) was incorrect.

Give a try this:

alias testt {
  if ($sock(testing)) { sockclose testing }
  sockopen -e testing 443
  ; sockmark test $1

on *:sockopen:testing: {
  if ($sockerr) { sockclose $sockname | return }
  sockwrite -nt $sockname POST /room_memberships?oauth_token=my_token&irc_channel=_my_channel_1433531105324&username=2nd_user_name HTTP/1.1
  sockwrite -n $sockname Host: $sock($sockname).addr
  sockwrite -n $sockname User-Agent: Mozilla/*
  sockwrite -n $sockname Connection: close
  sockwrite -nt $sockname $crlf

on *:sockread:testing:{
  if ($sockerr) { sockclose $sockname | return }
  sockread %temp
  if ($sockbr) { echo 2 -a READ: $left(%temp,4098) }

I cannot full test it because i dont have the oauth token.

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