Cant create two rx

GNU Radio
1

Hi all, I need to use two rx in my project, however I can not create two
rx.
My code create rx is bellow:

Rx1 = usrp_standard_rx_sptr(usrp_standard_rx::make(0,decimRate,1,-1,

usrp_standard_rx::FPGA_MODE_NORMAL,
1024,16*8,rbf));

Rx2 = usrp_standard_rx_sptr(usrp_standard_rx::make(0,decimRate,1,-1,

usrp_standard_rx::FPGA_MODE_NORMAL,
1024,16*8,rbf));

the error:
usrp_open_interface:usb_claim_interface: failed interface 2
could not claim interface 2: Device or resource busy
usrp_basic_rx: can’t open rx interface

2

The rule is one usrp_block per board. If you have two boards, you must
specify the which parameter = 0 for one board, = 1 for the other.

-Josh