## Crash Dump Analysis Patterns (Part 268)

When interpreting a value as a pointer to a memory address we are usually interested in adjacent values pointed to:

`0:000> ? rdx`

Evaluate expression: 982485297288 = 000000e4`c0afe888

`0:000> ? poi(000000e4`c0afe888)`

Evaluate expression: 180 = 00000000`000000b4

`0:000> ? poi(rdx)`

Evaluate expression: 180 = 00000000`000000b4

`0:000> dps rdx-10 rdx+10`

000000e4`c0afe878 000000e4`c0afeac0

000000e4`c0afe880 000000e4`c0971000

000000e4`c0afe888 00000000`000000b4

000000e4`c0afe890 00000000`0000008c

000000e4`c0afe898 00000000`00000088

`0:000> r $t0 = 0`

`0:000> dps rdx-@$t0 rdx+@$t0`

000000e4`c0afe888 00000000`000000b4

`0:000> r $t0 = 20`

`0:000> dps rdx-@$t0 rdx+@$t0`

000000e4`c0afe868 00000000`00000001

000000e4`c0afe870 00001a38`00000001

000000e4`c0afe878 000000e4`c0afeac0

000000e4`c0afe880 000000e4`c0971000

000000e4`c0afe888 00000000`000000b4

000000e4`c0afe890 00000000`0000008c

000000e4`c0afe898 00000000`00000088

000000e4`c0afe8a0 00000000`00000088

000000e4`c0afe8a8 00000000`0000008c

We call this analysis pattern **Pointer Cone** by analogy with cones in category theory and our earlier attempts to use it. The reason for this pattern appearance is that it has been used in many times in other analysis pattern descriptions. We also intend to use this pattern language building block in our next analysis pattern.

- Dmitry Vostokov @ DumpAnalysis.org + TraceAnalysis.org -