sercomm/osmocon cant send CMD after PROMPT1

I'm running into a problem with sercomm. oscmocon is unable to write() the CMD after PROMPT1 is received. I've attached a quick python client that checks from PROMPT1 and then sends CMD to confirm that it responds and its not something with the local system (OSX). Relevant code with some added debugging: static int handle_read(void) { if (!memcmp(buffer, phone_prompt1, sizeof(phone_prompt1))) { printf("Received PROMPT1 from phone, responding with CMD\n"); dnload.print_hdlc = 0; dnload.state = WAITING_PROMPT2; rc = write(dnload.serial_fd.fd, dnload_cmd, sizeof(dnload_cmd)); /* not in src, added for debugging: */ if (rc <= 0) { printf("error writing CMD to serial\n"); exit(1); } ... $ ./osmocon -m c155 -p /dev/tty.usbserial \ ../../target/firmware/board/compal_e99/hello_world.bin got 1 bytes from modem, data looks like: 1b got 6 bytes from modem, data looks like: f6 02 00 41 01 40 Received PROMPT1 from phone, responding with CMD could not write CMD to serial Output from python script: (if you try this, be sure to set your serial port and change the python2.5 call on line 1) $ ./compalserialtest.py 115200 got byte(s) from phone: 1b got byte(s) from phone: f6 got byte(s) from phone: 02 got byte(s) from phone: 00 got byte(s) from phone: 41 got byte(s) from phone: 01 recieved PROMPT1 from phone. Writing CMD got byte(s) from phone: 1b got byte(s) from phone: f6 got byte(s) from phone: 02 got byte(s) from phone: 00 got byte(s) from phone: 41 got byte(s) from phone: 02 got byte(s) from phone: 43 -- cyphunk://cypherpoet.com nathan://squimp.com fain://deadhacker.com