Merge pull request #568 from andyneff/docker

Documentation on PipeTransport to Docker

Documentation/Debugger/gdb/PipeTransport.md

@@ -26,4 +26,27 @@ You may also need to add a `sourceFileMap` to map the path of where the code exi
 ```
 
 ## Attach
-You can also use the above `pipeTransport` block to attach to a remote process. In the attach case, you will need to specify a `processId`. We have added the ability to query processes from the remote machine. To do this, change `"processId": "${command.pickProcess}"` to `"processId": "${command.pickRemoteProcess}"`. The `pipeTransport` settings will be used to query the processes on the remote machine. Then select the process from the drop down list. As with `launch`, you may need to configure `sourceFileMap`.  
+You can also use the above `pipeTransport` block to attach to a remote process. In the attach case, you will need to specify a `processId`. We have added the ability to query processes from the remote machine. To do this, change `"processId": "${command.pickProcess}"` to `"processId": "${command.pickRemoteProcess}"`. The `pipeTransport` settings will be used to query the processes on the remote machine. Then select the process from the drop down list. As with `launch`, you may need to configure `sourceFileMap`. 
+
+## Docker example
+
+The `pipeTransport` can also be used to debug a process in a Docker container. For an attach, the `launch.json` will include:
+
+```
+    "pipeTransport": {
+        "pipeCwd": "${workspaceRoot}",
+        "pipeProgram": "docker",
+        "pipeArgs": [
+            "exec", 
+            "-i", 
+            "hello_gdb", 
+            "sh",
+            "-c"
+        ],
+        "debuggerPath": "/usr/bin/gdb"
+    },
+```
+
+Where `hello_gdb` is the name of your container.
+
+Launching a process is accomplished by starting a container and then using the same `pipeTransport` launch additional processes in the container. See this [`launch.json`](https://github.com/andyneff/hello-world-gdb/blob/master/.vscode/launch.json) for a [full example](https://github.com/andyneff/hello-world-gdb/)