I may be struggling with a similar issue:
I need to send a string terminated with “\r\n”, but it appears that socket_send_line only appends \n. I have tried concatenating “\r” to the end of my string, but the socket_send_line function seems to add an extra \. << even right here, i had to type two backslashes to get it to display one. this is expected with escape sequences, but undesired when sending byte strings
edit: i found this today, havent tried it yet: TCP socket line terminator