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2020-01-18 20:44:36 -0500 marked best answer Why does not catkin_make work?

I have two versions of src file in the package under the workspace. I ran one and named the other src2 (CmakeList.txt compiles the source file in src directory). Then I want to run the other version files, so src is renamed to src1 and src2 is renamed to src, and I ran catkin_make in the workspace, but there is no new file generated and when I start the node, it' s still the old one. It's so weird. Can someone explain it?

2020-01-18 20:43:47 -0500 marked best answer rospy.wait_for_message is unable to subscribe to a message

rospy.wait_for_message can receive one message from topic. It will create a new subscription to the topic, receive one message, then unsubscribe. But when I try to use it, the function can't work at all. For example,

roscore &
rostopic pub -r 1 /data std_msgs/Float32 2.0

the use this function to subscribe once:

import rospy
from std_msgs.msg import Float32
rospy.wait_for_message('/data', Float32)

It will be stuck here and there is no response at all. But if we subscribe directly

rostopic echo /data

It can work. What's the matter with this function? And I try to test it on different computers and ROS version, the result is the same.

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2019-08-21 07:51:31 -0500 edited question Why does not catkin_make work?

Why dose not catkin_make work? I have two versions of src file in the package under the workspace. I ran one and named t

2019-08-21 07:51:28 -0500 edited question Why does not catkin_make work?

Why does catkin_make dose not work? I have two versions of src file in the package under the workspace. I ran one and na

2019-08-21 07:49:44 -0500 asked a question What's the mechanism of the header timestamp of ROS message?

What's the mechanism of the header timestamp of ROS message? I'm curious about the mechanism of the header timestamp of

2019-08-21 07:47:37 -0500 asked a question Why does not catkin_make work?

Why does catkin_make dose not work? I have two versions of src file in the package under the workspace. I ran one and na

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2019-03-10 09:11:08 -0500 asked a question python API for roslaunch with parameter

python API for roslaunch with parameter I want to run a roslaunch file with parameter, I follow this tutorial: import r

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2019-01-17 08:44:18 -0500 answered a question rospy.wait_for_message is unable to subscribe to a message

just add rospy.init_node('test') before.

2019-01-17 08:42:53 -0500 edited question rospy.wait_for_message is unable to subscribe to a message

rospy.wait_for_message is unable to subscribe to a message rospy.wait_for_message can receive one message from topic. It

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2019-01-17 08:42:24 -0500 edited question rospy.wait_for_message is unable to subscribe to a message

rospy.wait_for_message is unable to subscribe to a message rospy.wait_for_message can receive one message from topic. It

2019-01-17 04:06:39 -0500 asked a question rospy.wait_for_message is unable to subscribe to a message

rospy.wait_for_message is unable to subscribe to a message rospy.wait_for_message can receive one message from topic. It