The centos-art.sh script follows a conventional command-line interface where there might be options and non-option arguments in it. As convention, the first non-option argument passed to centos-art.sh script will be the name of the specific function you want to execute (e.g., render, locale, help, etc.). This first argument will be immediately removed from the list of arguments passed to centos-art.sh script to leave just the remaining options and non-option arguments passed to it. At this point, the centos-art.sh script uses the getopt command to retrieve option arguments and remove them from the list of arguments passed to centos-art.sh script. Once option arguments have been removed from list of arguments passed to centos-art.sh script, non option arguments are processed then. Non-option arguments will always be paths pointing directories inside your working copy of &TCAR;. These paths can be absolute paths or relative paths considering the working copy root directory as section. For example, both the absolute path /home/al/Projects/CentOS/artwork/trunk/Identity/Themes/ and the relative path trunk/Identity/Themes point to the same location.

To better understand the centos-art.sh command-line interface, let's consider the real command shown in as section. This command shows the entire command as a list of space-separated arguments. The value of each argument can be reached using special variable names based on the number of arguments passed to the command-line. The command-line interface ${0} | |${1}| | ${2} | | ${3} | ---------|-|----|-|--------------------------|-|-----------| centos-art render trunk/Identity/Images/Themes --with-brands ---------|-|----|-|--------------------------|-|-----------| In , the relation between special variables and arguments has the following meaning: ${0} This variable contains the absolute path to the command executed. In case your home directory be /home/john the value of this argument will be expanded to /home/john/bin/centos-art which is a symbolic link to the ${TCAR_WORKDIR}/trunk/Scripts/Bash/centos-art.sh file. ${1} This variable contains the first non-option argument we use to determine the specific function environment we want to execute (e.g., render in this case). The position of this information in the command-line is relevant to centos-art.sh script and must not be changed. Possible values to this variable are specified in . ${2} This variable contains a non-option argument referring a path information inside the working copy of &TCAR;. The specific path information you provide in this variable must be recognized by specific function environment provided in ${1} variable. The position of path information in the command-line is not relevant to centos-art.sh script and can be changed whenever it doesn't be interpreted as value to ${1} variable. ${3} This variable contains an option argument. The specific option information you provide in this variable must be recognized by specific function environment provided in ${1} variable. The position of options in the command-line is not relevant to centos-art.sh script and can be changed whenever it doesn't be interpreted as value to ${1} variable.

As convention, all function specific environments should provide support for the following common options: -h | --help This option makes centos-art.sh script to shows information about the specific function environment (e.g., how to execute it, available options, etc.) set as first non-option argument. For example, if you provide the centos-art render --help, the centos-art.sh script will display to you the information related to the trunk/Scripts/Bash/Functions/Render directory. This information is retrived from The CentOS Artwork Repository File System (tcar-fs) documentation manual. This manual is written in Texinfo format and provides a quick way for you to read and browse documentation related to each directory inside &TCAR; as you work with it from a text terminal. -q | --quiet This option makes the centos-art.sh script to suppress messages sent to standard output. This option doesn't suppress error messages, nor questions related to script execution.

The specific options used by specific and common function environments are described in their respective sections. See and to know which these sections are. Name Description prepare render locale help pack tuneup svn Name Description cli_checkFiles

When a new function is created to centos-art.sh script, it is necessary to consider whether it will use arguments or not. When the function doesn't need arguments (e.g., it exists to redefine values related to global variables only) there is no need to consider a parsing feature for it. However, when the function does use arguments it is very important to parse them appropriately (e.g., by using a parsing feature like that provided by getopt command). In this section will describe how to parse arguments (both option and non-option) inside the centos-art.sh script. This information must be used as section whenever you need to create a new function for centos-art.sh script.