T265 can only be accessed by the first pipe instantiated

[stephen-systemfriend]

---

|---------------------------------|------------------------------------------- |
| Camera Model | T265|
| Operating System & Version | Win 10 |
| Platform | PC/Raspberry Pi/ NVIDIA Jetson / etc.. |
| SDK Version | 2.20 |
| Language | C } |

If you create multiple rs::pipe objects, only the first one can find the T265. I think that they must be locking it in the constructor somewhere.

heres a MWE

`
#include
#include <librealsense2/rs.hpp>

int main()
{
std::string T265_serial = "845412110352";
std::string D435i_serial = "838212070412";
//if you swap these two, it will no longer run
rs2::pipeline T265_pipe;
rs2::pipeline D425i_pipe;
rs2::config T265_cfg, D435i_cfg;

D435i_cfg.enable_device(D435i_serial);
T265_cfg.enable_device(T265_serial);
// Add pose stream
T265_cfg.enable_stream(RS2_STREAM_POSE, RS2_FORMAT_6DOF);

try
{
	T265_pipe.start(T265_cfg);
	D425i_pipe.start(D435i_cfg);
}
catch (std::exception e)
{
	std::cout << "failed to start pipes with error: " << e.what() << std::endl;
	return -1;
}

//diplay the stream
for (int i = 0; i < 200; i++) {
	//pose
	auto pose_frames = T265_pipe.wait_for_frames();
	auto f = pose_frames.first_or_default(RS2_STREAM_POSE);
	auto pose_data = f.as<rs2::pose_frame>().get_pose_data();
	std::cout << "Device Position: "  << std::fixed << pose_data.translation.x << " "
		<< pose_data.translation.y << " " << pose_data.translation.z << " (meters)" << std::endl;
	//depth
	auto depth_frames = D425i_pipe.wait_for_frames();
	auto df = depth_frames.get_depth_frame();
	std::cout << "Depth Disparity: " << df.get_distance(10, 100) << std::endl;

}
return 0;

}
`

[ev-mp]

@stephen-systemfriend hello,
Currently all the connected T265 sensors are registered on startup with the first rs2::context created.
Hence, in order to to open multiple pipes that rs2::context should be shared among these pipes. It is achieved by passing the rs2::context to each pipe created.

rs2::context ctx;
for (auto&& dev : ctx.query_devices())
{
rs2::pipeline pipe(ctx);
...

Refer to multicam example for the full code.

Links to #3434, #3437

[ev-mp]

@stephen-systemfriend , do you need more assistance with this ?

[stephen-systemfriend]

the fix was perfect, thank you

[karry3775]

Were you able to launch multiple t265 with the help of ros. I am currently using realsense-ros package to launch one t265 (demo_t265.launch). I tried using the (rs_multiple_devices.launch) file, but it doesn't support two t265s at the time. Was there a fix you could find. Thank you

[stephen-systemfriend]

@karry3775 I only had one t265 plugged in, so what you have is a different issue that you should probably open separately

[karry3775]

Thank you for your response. I will open a new issue in that case.

…

On Tue, Jan 14, 2020, 6:19 PM stephen-systemfriend ***@***.***> wrote: @karry3775 <https://github.com/karry3775> I only had one t265 plugged in, so what you have is a different issue that you should probably open separately — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#3734?email_source=notifications&email_token=AKLHQT3PQQW7Y3Y4UMTPKMLQ5ZJBJA5CNFSM4HFCIOL2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEI6TKEI#issuecomment-574436625>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AKLHQT2VFDPAI6D54K5DJUDQ5ZJBJANCNFSM4HFCIOLQ> .