How to extract variable def-use relations ?

[Bowen-n]

Variable def-use: For example, a variable is defined by mox ebx 0x1, and then it is used by mov rdx rbx which can be far from mox ebx 0x1. Then, these two instructions have a def-use relation.

In Radare2 command line, how to extract all the variable def-use relations between instructions inside a function ?