This topic lists and describes the Dockerfile.Debug file from the Hello World Docker demonstration. The Dockerfile is listed in its entirety and a following table describes the various Dockerfile commands. The line numbers in the listings of the Dockerfile have been added to aid readability. They are not present in the supplied Dockerfile.
001  # Copyright (C) Micro Focus 2018. All rights reserved. 
002  # This sample code is supplied for demonstration purposes only
003  # on an "as is" basis and is for use at your own risk. 
004  
005  ARG DTAG
006  FROM microfocus/cobolserver:${DTAG}
007  
008  # not used
009  ARG PLATFORM
010  
011  # optional arguments
012  ARG APPDIR=c:\\app
013  
014  # set the start directory
015  WORKDIR "${APPDIR}"
016  
017  EXPOSE 6100 
            	 The commands on the lines in this Dockerfile are as follows:
| Lines | Description | 
|---|---|
| 005 - 006 | Specifies the base image to use, which is the COBOL Server base image. | 
| 009 - 012 | Define build arguments passed by the 
                              			 docker build command: 
 | 
| 015 | Sets the Docker working directory to be the folder for the Hello World application in the image's filesystem. | 
| 017 | Specifies the network ports that the container will listen on at run-time. |