Platform Notes (Mac OS X)

Port Status

The Mac OS X port is a Tier 3 Port, though it can run with some significant headaches.

The main branch will compile on macOS Monterey (12.6.8) on Intel, and it can run if the kern.sysv.shmmax parameter is correct (see below). Launching new interpreters can be hit-or-miss, as there are shared memory issues on this platform. You may need to try starting a new process 10 times or more before one will launch successfully.

FreeM Lite works correctly on this platform, bugs in that release notwithstanding.

Verified Releases

• FreeM Lite

Build Notes

In order to build FreeM on macOS, you will need to install the following:

• Apple XCode command-line tools
• Homebrew

Then, install the following with the brew package manager:

• automake
• autoconf
• gcc
• libtool
• texinfo
• texi2html
• git

Testing Details

We build the macOS port on the following hardware:

• MacBook Air (Early 2015) running macOS Monterey (12.6.8)

Required Kernel Tuning

You will need to set the kern.sysv.shmmax sysctl parameter to at least 6144000 (the value must be a multiple of the system page size; generally 4096).

To determine the current setting, see below:

$ sudo sysctl -a | grep shmmax
kern.sysv.shmmax: 4194304

In the above example, the shmmax value is 4194304, and thus insufficient for proper FreeM operation.

See your macOS version below for instructions on modifying this value.

macOS Monterey

• Find the file com.startup.sysctl.plist file in the scripts subdirectory of the FreeM distribution
• Copy it to /Library/LaunchDaemons
• Change the ownership of /Library/LaunchDaemons/com.startup.sysctl.plist to root:wheel
• Run sudo launchctl load /Library/LaunchDaemons/com.startup.sysctl.plist
• Reboot

See the following example:

$ sudo cp scripts/com.startup.sysctl.plist /Library/LaunchDaemons/
$ sudo chown root:wheel /Library/LaunchDaemons/com.startup.sysctl.plist
$ sudo launchctl load /Library/LaunchDaemons/com.startup.sysctl.plist

Starting the FreeM Daemon Automatically

Coming soon.

Port Challenges

Apple makes it extremely difficult to build traditional UNIX software, in the name of "security". Also, Apple silicon (M1 and descendants) cannot likely be supported with the current shared memory architecture.

We will most likely support only PowerPC and Intel Macs.