Fix PR comments

Signed-off-by: Prasanna Bhat <prasanna.yoga@gmail.com>

scripts/build.sh

@@ -6,9 +6,46 @@ WORKSPACE=$(pwd)
 echo "WORKSPACE is $WORKSPACE"
 
 CYCLONEDDS_INSTALL_PREFIX=$WORKSPACE/build/install/
+CLEAN_BUILD=false
 
-rm -rf build/
+usage() {
-mkdir build
+	echo ""
+	echo "Helper script to build cyclonedds"
+	echo "Usage : "
+	echo "<workspace>/scripts/build.sh [options]"
+	echo "Supported options are "
+	echo "clean 		: remove build folder (Default : keep build folder)"
+	echo ""
+}
+
+parse_args() {
+	for arg in "$@"
+	do
+		case $arg in
+		    -h | --help)
+			usage
+			exit 0
+			;;
+			clean)
+			CLEAN_BUILD=true
+			;;
+			*)
+			echo "ERROR : unknown parameter $arg"
+			usage
+			exit 1
+			;;
+		esac
+	done
+}
+
+parse_args $@
+
+if [ $CLEAN_BUILD == true ]
+then
+    rm -rf build/
+fi
+
+mkdir -p build
 cd build
 cmake -DCMAKE_INSTALL_PREFIX=$CYCLONEDDS_INSTALL_PREFIX -DBUILD_IDLC=ON ..
 cmake --build .

scripts/docker/DockerfileCycloneDds

@@ -5,4 +5,4 @@ ADD . /cyclonedds
 
 WORKDIR /cyclonedds
 
-RUN ./scripts/build.sh
+RUN ./scripts/build.sh clean

scripts/docker/README.md

@@ -1,7 +1,7 @@
 # Overview
 
 This contains helper scripts to build & run cyclonedds core & example applications in docker.  
-Additionally you can also build a docker image with pre-built cyclonedds examples. This could be useful in quikly trying the examples (both IPC & network communication).
+Additionally you can also build a docker image with pre-built cyclonedds examples. This could be useful in quickly trying the examples (both IPC & network communication).
 
 # Bulid docker image 
 There are two docker images you can build.  
@@ -27,6 +27,7 @@ The following images are supported.
 `ubuntu` : Same as **ubuntu:cyclonedds** , mentioned above.  
 `cyclonedds` : Same as **cyclonedds:latest**, mentioned above.  
 You can run the script with `-h` option to display usage information.  
+**NOTE** : *cyclonedds:latest* depends on image *ubuntu:cyclonedds*. You need to build *ubuntu:cyclonedds* first, if you want to use *cyclonedds:latest*.  
 - Build cyclonedds core & examples (if you are using **ubuntu:cyclonedds**)  
 Use the helper script `./scripts/docker/build_cyclonedds.sh` to build using the currently checked out revision.  
 **NOTE** : You need to run this script from the root of the project.
@@ -40,13 +41,16 @@ Let's do that !
   
 ## Run examples inside the same container (uses IPC)  
 - Launch docker container, from the root of the project  
-`docker run --name cyclonedds -it -v $(pwd):/cyclonedds --workdir /cyclonedds cyclonedds:latest /bin/bash`
+
-This will open terminal connected to docker @ root of the project.  
+```
+docker run --name cyclonedds -it --workdir /cyclonedds/build/bin cyclonedds:latest /bin/bash
+```
+This will open terminal connected to docker @ bin of the project, which contains sample applications.
 It will look something like this
 ```
-root@22ff409a33e1:/cyclonedds# 
+root@22ff409a33e1:/cyclonedds/build/bin# 
 ```
-- Navigate to `/build/bin` to run the example applications.
+- From here you can run the example applications.
 - To run another terminal , connected to same docker container, use the following command.
 ```
 docker exec -it cyclonedds /bin/bash
@@ -57,7 +61,7 @@ Run the partner example here. This will establish communication over IPC channel
 ## Run examples in different containers (uses docker networking)
 - Follow the same steps as in the previous section , instead connecting to existing docker container create a new docker container.
 e.g.  
-`docker run --name cyclonedds1 -it -v $(pwd):/cyclonedds --workdir /cyclonedds cyclonedds:latest /bin/bash`  
+`docker run --name cyclonedds1 -it --workdir /cyclonedds/build/bin cyclonedds:latest /bin/bash`  
 **NOTE** : You need to run this script from the root of the project.  
 At this point you can inspect the traffic using wireshark.  
 Open docker network interface (`docker0` on my system) in wireshark.  

scripts/docker/build_cyclonedds.sh

@@ -9,7 +9,7 @@ CONTAINER_NAME="cyclonedds"
 
 echo "WORKSPACE is $WORKSPACE"
 
-docker run -it --rm -v $WORKSPACE/:/cyclonedds --workdir /cyclonedds $IMAGE_NAME /bin/bash -c "./scripts/build.sh"
+docker run -it --rm -v $WORKSPACE/:/cyclonedds --workdir /cyclonedds $IMAGE_NAME /bin/bash -c "./scripts/build.sh clean"
 # Launch the docker after build
 docker run --name $CONTAINER_NAME -it -v $WORKSPACE/:/cyclonedds --workdir /cyclonedds $IMAGE_NAME /bin/bash
 # If you want to connect to the above docker to run cyclonedds examples (multiple apps in separate terminals) , use the below command