TSE: Linux: Watcom: How to install Open WatCom version 2.x on Linux WSL Ubuntu?

[knud van eeden]

 Q. TSE: Linux: Watcom: How to install Open WatCom version 2.x on Linux WSL Ubuntu?

Hello,

FYI:

Given: TSE for Linux itself is where applicable compiled (only) with Open WatCom 2.x.

Note: When facing selection choices they must be WatCom 2.x 32 bit compatible, because TSE for Linux is 32 bits

===

You can find the downloadable WatCom 2.x versions at this URL:

https://github.com/open-watcom/open-watcom-v2/releases

There choose a release

(Note: I chose the latest release from January 2026, because the older

       version had some serious issues. Even with the latest WatCom

       version very frequently 'segmentation fault' when compiling. It

       showed that 'fflush()' in C was the culprit).

Use there such a file and download it.

 ow-snapshot.tar.xz

===

Steps to install "Open Watcom C/C++ x86 32-bit Compile and Link Utility Version 2.0 beta"

1. -Run

     cmd.exe

2. -Run

     wsl

3. -Then inside Linux WSL Ubuntu

4. -Advice: Copy these steps #1, #2, #3, ... one after on the wsl

            command prompt and await and view the result each time.

5. -Using these steps an installation takes typically a few minutes here

    and the installation of WatCom 2.x was successful using these steps.

--- cut here: begin --------------------------------------------------

# 1) First set once your userid to sudo

sudo usermod -aG sudo $USER

# 2) Completely remove any previous Watcom installation: directories

sudo rm -rf /opt/watcom

sudo rm -rf /usr/watcom

sudo rm -rf /usr/local/watcom

sudo rm -rf ~/watcom

# 3) Completely remove any previous Watcom install: environment variables from the shell startup

sed -i '/WATCOM/d' ~/.bashrc ~/.profile ~/.bash_profile 2>/dev/null

# 4) Verify nothing Watcom-related remains:

which wcc wcc386 wcl wcl386 2>/dev/null

env | grep -i watcom

ls /opt | grep -i watcom

# 5) Go to a download folder

cd /tmp

# 6) First remove any existing ow-snapshot.tar.xz file, because otherwise they will be created with xz1, xz2, ... file extensions

rm /tmp/ow-snapshot.tar.*

# 7) Download the specific snapshot you want

#

# this is the Semware version from 2 August 2025

# wget https://github.com/open-watcom/open-watcom-v2/releases/download/2025-08-02-Build/ow-snapshot.tar.xz

#

# Using the newest version from 11 January 2026

wget https://github.com/open-watcom/open-watcom-v2/releases/download/Last-CI-build/ow-snapshot.tar.xz

# 8) Install into /opt/watcom

sudo mkdir -p /opt/watcom

# 9) Extract it to /opt/watcom

sudo tar -xJf ow-snapshot.tar.xz -C /opt/watcom

# 10) Verify layout of /opt/watcom/ after the extraction

ls /opt/watcom

# 11) Add environment variables so you use 32-bit tools only

cat >> ~/.bashrc <<EOF

export WATCOM=/opt/watcom

export PATH="\$WATCOM/binl:\$PATH"

export INCLUDE="\$WATCOM/h"

export LIBPATH="\$WATCOM/lib386/linux:\$WATCOM/lib386"

EOF

# 12) Reload your shell config

# Also update current shell OR start new shell

exec bash

source ~/.bashrc

# 13) Install 32-bit libraries

sudo dpkg --add-architecture i386

sudo apt update

sudo apt install -y libc6:i386 libstdc++6:i386

# 14) Verify correct binaries

which wcc wcl386

file $(which wcc)

file $(which wcl386)

# Expected result here = ELF 32-bit LSB executable, Intel 80386

# 15) Remove any old hello files

rm /tmp/hello.*

# 16) Build & run a real test (the important part)

cat > hello.c <<'EOF'

#include <stdio.h>

int main(void) {

    char buf[10];

    puts("Hello Open Watcom v2 (32-bit) on WSL");

    printf("Type something: ");

    if (fgets(buf, sizeof(buf), stdin)) {

        printf("You typed: %s", buf);

    }

    return 0;

}

EOF

# compile it

wcl386 hello.c

# run it

./hello

# Expected output: # "Hello Open Watcom v2 (32-bit) on WSL"

--- cut here: end ----------------------------------------------------

with friendly greetings

Knud van Eeden