email - Gmail Set Headers with API -

i trying set dummy headers using gmail api. per thread (correct email headers delivering mailing list mail) rcpt , headers quite different. , if rcpt header set header should used showing user , not actual sending. when setting headers gmail sends email "to" header , not rcpt to.

this trying:

rcpt to: actual_to <to@recipient.com> from: sender <sender@sender.com>  to: dummy_to <dummy@dummy.com>  subject: saying hello    message hello. so, "hello". 

encoding , sending via gmail api.

post https://www.googleapis.com/gmail/v1/users/arpan%40intricare.net/messages/send?fields=raw&key={your_api_key} {  "raw": "uknqvcbutzogywn0dwfsx3rvidx0b0byzwnpcgllbnqclrsuy29tpgpgcm9toibtzw5kzxigphnl bmrlckbzzw5kzxiuy29tpiakvg86ier1bw15x3rvidxkdw1teubkdw1tes5jb20-iaptdwjqzwn0 oibtyxlpbmcgsgvsbg8gciagicakvghpcybpcybhig1lc3nhz2uganvzdcb0bybzyxkgagvsbg8u ifnvlcaisgvsbg8ilg==" } 

google groups uses same concept send emails list of people still use field list name.

unless can point in documentation, don't believe gmail api in way honors rcpt header. try:

bcc: <to@recipient.com> to: <dummy@dummy.com> 

this send both addresses. assuming dummy.com exist , don't want send mail you'll need use direct smtp connection smtp.gmail.com keep rcpt , header entirely independent of each other.