General notes about MacOS

The Keyboard under MacOS

Table 1. Apple Tasten
⌘	⌥	⇧
Command key	Option key	Shift key
"command"	"option"	"shift"
CMD	CTRL

Table 2. Sonderzeichen
Special character	Designation	Key combination
@	At	cmd + L
€	Euro	alt + E
$	Dollar	shift + 4
£	British Pound	alt + shift + 4
©	Copyright	alt + G
®	Registered	alt + R
™	Trademark	alt + shift + D
?	Apple	alt + shift + +
§	Paragraph	shift + 3
~	Tilde	alt + N (dann Leertaste)
(	opening Bracket	shift + 8
)	closing Bracket	shift + 9
[	opening Square bracket	alt + 5
]	closing Square bracket	alt + 6
{	opening Curly bracket	alt + 8
}	closing Curly bracket	alt + 9
/	Slash	shift + 7
\	Backslash	alt + shift + 7
		Pipe (vertical line)
alt + 7	„	Right double quote
alt + ^	“	Left double quote
alt + shift + ^	‚	Comma
alt + S	‘	Single quote
alt + #	»	Double right angle quotation mark
alt + shift + Q	«	Double left angle quotation mark
alt + Q	›	Single right angle quotation mark
alt + shift + N	‹	Single left angle quotation mark
alt + shift + B	=	Equal
shift + 0	≠	Unequal
alt + 0	≤	Less than equal
alt + >	≥	Greater than equal
alt + shift + >	>	Greater
shift + >	<	Smaller
fn + >	±	Plus or minus
alt + +	≈	Approximate
alt + X	ø	Average
alt + O	∞	Infinity
alt + ,	%	Percent
shift + 5	π	Pi
alt + P	√	Check mark

https://www.heise.de/tipps-tricks/Mac-Sonderzeichen-Mit-diesen-Tastenkombinationen-klappt-s-3996796.html

The opsi product m-homebrew

There are a number of package management programs for MacOS, which allow to provide common Unix programs under MacOS. Typical examples of this package management programs are:

The opsi product m-homebrew installs the homebrew system on a MacOS system.

homebrew installs the command brew on the system, which allows then programs to be downloaded from the Internet. Either a binary is installed directly or the sources are downloaded and the program is compiled on the machine. Therefore homebrew also needs the development command line tools to compile programs (xcode-select --install).

For security reasons homebrew is conceived to not be executed as root, but only with user rights. To ensure this in the opsi context a hidden user named opsisetupadmin is created during the installation of the opsi-client-agent (see also The MacOS pseudo user opsisetupadmin).
This user owns the whole homebrew system on the machine and therefore, only this user should be used to perform the installation of software on the machine via the brew command.
I.e. The brew command should be executed as root as follows:

sudo -H -u opsisetupadmin /usr/local/bin/brew

For example, the installation of Java in the product m-javavm is implemented as follows:

[ShellScript_brew_install_java]
; https://github.com/SAP/SapMachine/wiki/Installation
EXITCODE=0
sudo -H -u opsisetupadmin /usr/local/bin/brew tap sap/sapmachine
EC=$?; if [ $EC -ne 0 ]; then EXITCODE=$EC; fi
sudo -H -u opsisetupadmin /usr/local/bin/brew install --cask sapmachine-jdk
EC=$?; if [ $EC -ne 0 ]; then EXITCODE=$EC; fi
exit $EXITCODE

To find out if the installation of a desired product is supported via homebrew, it is best to use the following website:
https://formulae.brew.sh/

Helpful links for homebrew:
https://formulae.brew.sh/

Additional helpful Links for homebrew:
https://docs.brew.sh/
https://devhints.io/homebrew

The MacOS pseudo user opsisetupadmin

When installing the opsi-client-agent a 'hidden user' named opsisetupadmin is created. This user has no password and cannot be used for login.

The home directory of this user is /var/lib/opsisetupadmin.

This user is employed for the following purposes:

Operating the homebrew system (see The opsi product m-homebrew).
The directory /var/lib/opsisetupadmin/opsi_depot is the mount point on which the opsiclientd mounts the depotshare.
This is done since access to network shares not mounted in a user directory are very limited.

The opsi directories on MacOS

Essential opsi directories and files on the MacOS client

/var/log/opsi-script (Log files opsi-script)
/var/log/opsi-client-agent (other opsi Log files)
/usr/local/bin/opsi* (Command line programs)
/Applications/opsi-script-gui.app
/Applications/opsi-notifier.app
/etc/opsi-client-agent (Configuration opsi-client-agent)
/etc/opsi-script (Configuration opsi-script)
/usr/local/lib (Help libraries e.g. ssl)
/usr/local/lib/opsiclientd
/usr/local/bin/locale (local opsi-script)
/usr/local/share/opsi-client-agent
/usr/local/share/opsi-script
/usr/local/share/notifier.d
/var/opsisetupadmin (Home directory opsisetupadmin)
/var/lib/opsi-client-agent
/Library/LaunchDaemons/ (Start configuration for opsi deamons)
/Library/LaunchAgents/ (Start configuration for opsi-systray)

MacOS directory structure with 'go' and 'nogo'.

MacOS is based on BSD-Unix and has a typical Unix file system structure. However, due to security reasons, there are several areas that are exclusively reserved for Apple and a few other specifics that are important for the person doing the packaging work:

/Applications
This is the directory where the graphical applications are located. An application consists of a directory <Application name>.app. Such a directory is not shown in the Finder as a directory, but as an 'Application'. Inside this directory the files of the application must be located according to a certain specific pattern.
/sbin, /bin, /usr/bin, /usr/share, /usr/lib
These are apple only directories into which nobody else is allowed to copy anything. Use instead the local variants:
/usr/local/bin, /usr/local/share, /usr/local/lib