Find path to ROS executable

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Is there a command to find the path to a ROS executable without running it?

I looked for roswhich similar to cd/roscd and cp/roscp
https://linux.die.net/man/1/which

I found that rosrun takes a non-trivial amount of time to find an executable. When running a command often, I plan to cache the path to executable and not use rosrun.
Single binary workspace: 30ms
Single source workspace: 110ms

Test setup:

time rosrun some_package empty_file
time /path/to/ros_workspace/src/some_package/empty_file