4.2. POSIX Hosts — RTEMS User Manual 5.4-rc2 (21st August 2026) documentation

# 4.2. POSIX Hosts

POSIX hosts are most Unix operating systems such as Linux, FreeBSD and NetBSD. RTEMS development works well on Unix and can scale from a single user and a desktop machine to a team with decentralised or centralised development infrastructure.

## 4.2.1. Root Access

You either have `root` access to your host development machine or you do not. Some users are given hardware that is centrally managed. If you do not have `root` access you can create your work environment in your home directory. You could use a prefix of `$HOME/development/rtems` or `$HOME/rtems`. Note, the `$HOME` environment variable can be substituted with `~`.

Choose an Installation Prefix details using Prefixes to manage the installation.

RTEMS Tools and packages do not require `root` access to be built and we encourage you to not build the tools as `root`. If you need to control write access then it is best to manage this with groups assigned to users.

If you have `root` access you can decide to install the tools under any suitable prefix. This may depend on the hardware in your host development machine. If the machine is a centralised build server the prefix may be used to separate production versions from the test versions and the prefix paths may have restricted access rights to only those who manage and have configuration control of the machine. We call this project sandboxing and Project Sandboxing explains this in more detail.

## 4.2.2. Linux

BSP Build will require `pax` package if RTEMS is configured with the `--enable-tests` option, see Building RTEMS Tests. This package is not installed , by default, on many Linux distributions, you can check for it using your package manager. Install it, if it is not present on your system.

A number of different Linux distrubutions are known to work. The following have been tested and report as working.

### 4.2.2.1. ArchLinux

The following packages are required on a fresh Archlinux 64bit installation:

    # pacman -S base-devel gdb xz unzip ncurses git zlib

Archlinux, by default installs `texinfo-5` which is incompatible for building GCC 4.7 tree. You will have to obtain `texinfo-legacy` from `AUR` and provide a manual override:

    # pacman -R texinfo
    $ yaourt -S texinfo-legacy
    # ln -s /usr/bin/makeinfo-4.13a /usr/bin/makeinfo

### 4.2.2.2. CentOS

The following packages are required on a minimal CentOS 6.3 or Cent)S 7 64-bit installation:

    # yum install autoconf automake binutils gcc gcc-c++ gdb make patch pax \
    bison flex xz unzip ncurses-devel texinfo zlib-devel python-devel git

On CentOS 8, the `pax` command is now provided by the `spax` package, you need to enable the PowerTools repository. and use Python3. On a fresh install, the following commands should install everything you need for RTEMS development:

    # dnf install yum-utils
    # dnf config-manager --set-enabled PowerTools
    # dnf update
    # dnf groupinstall "Development Tools"
    # dnf install python3 python3-pip python3-setuptools python3-devel
    # dnf install texinfo spax
    # alternatives --set python /usr/bin/python3

The minimal CentOS distribution is a specific DVD that installs a minimal system. If you use a full system some of these packages may have been installed.

### 4.2.2.3. Fedora

The RTEMS Source Builder has been tested on Fedora 19 64bit with the following packages:

    # yum install ncurses-devel python-devel git bison gcc cvs gcc-c++ \
         flex texinfo patch perl-Text-ParseWords zlib-devel

### 4.2.2.4. Raspbian

The is the Debian distribution for the Raspberry Pi. The following packages are required:

    $ sudo apt-get install autoconf automake bison flex binutils gcc g++ gdb \
    texinfo unzip ncurses-dev python-dev git

It is recommended you get Model B of the Pi with 512M of memory and to mount a remote disk over the network. The tools can be built on the network disk with a prefix under your home directory as recommended and end up on the SD card.

### 4.2.2.5. Ubuntu

The latest version is Ubuntu 18.04.1 LTS 64-bit. This section also includes Xubuntu. A minimal installation was used and the following packages installed:

    $ sudo apt-get build-dep build-essential gcc-defaults g++ gdb git \
    unzip pax bison flex texinfo unzip python3-dev libpython-dev \
    libncurses5-dev zlib1g-dev

Note that in previous versions of Ubuntu, the package libpython-dev was python2.7-dev. The name of packages changes over time. You need the package with Python development libraries for C/C++ programs. The following is needed for recent versions:

    $ sudo apt-get install python-dev

It is likely necessary that you will have to enable the Ubuntu Source Repositories. Users have suggested the following web pages which have instructions:

- https://askubuntu.com/questions/158871/how-do-i-enable-the-source-code-repositories/158872

- https://askubuntu.com/questions/496549/error-you-must-put-some-source-uris-in-your-sources-list

### 4.2.2.6. Linux Mint

zlib package is required on Linux Mint. It has a different name (other than the usual zlib-dev):

    # sudo apt-get install zlib1g-dev

### 4.2.2.7. openSUSE

This has been reported to work but no instructions were provided. This is an opportunity to contribute. Please submit any guidance you can provide.

## 4.2.3. FreeBSD

The RTEMS Source Builder has been tested on FreeBSD 9.1, 10.3, 11 and 12 64bit versions. You need to install some ports. They are:

    # pkg install -y python
    # pkg install -y gsed

FreeBSD’s default C compiler is LLVM and installing the host’s GCC compiler package may break building GCC. We recommend you do not install the GCC package and you use the default C compiler.

If you wish to build Windows (mingw32) tools please install the following ports:

    # pkg install -y mingw32-binutils mingw32-gcc
    # pkg install -y mingw32-zlib mingw32-pthreads

The zlip and pthreads ports for MinGW32 are used when builiding a Windows QEMU.

Check if your kernel has a `/dev/fd` directory. If it does not we recommend you run as root the following command to speed up Python 3’s subprocess support:

    # mount -t fdescfs none /dev/fd

The support speeds up closing file descriptors when creating subprocesses.

## 4.2.4. NetBSD

The RTEMS Source Builder has been tested on NetBSD 6.1 i386. Packages to add are:

    # pkg_add ftp://ftp.netbsd.org/pub/pkgsrc/packages/NetBSD/i386/6.1/devel/gmake-3.82nb7.tgz
    # pkg_add ftp://ftp.netbsd.org/pub/pkgsrc/packages/NetBSD/i386/6.1/devel/bison-2.7.1.tgz
    # pkg_add ftp://ftp.netbsd.org/pub/pkgsrc/packages/NetBSD/i386/6.1/archivers/xz-5.0.4.tgz