When trying to change locale settings in Debian, many developers encounter situations where commands like LC_ALL=nl_NL date don't produce localized output. This typically happens because the specific locale hasn't been generated on the system.

# Check available Dutch locales
locale -a | grep nl_

If this returns no output or doesn't include nl_NL.utf8, you'll need to generate it.

Here's how to properly set up Dutch locale support:

# 1. Install locales package (if not already installed)
sudo apt-get install locales

# 2. Uncomment nl_NL.UTF-8 in /etc/locale.gen
sudo nano /etc/locale.gen
# Find and uncomment: nl_NL.UTF-8 UTF-8

# 3. Generate the locale
sudo locale-gen

# 4. Verify the locale is now available
locale -a | grep nl_NL

For system-wide changes affecting all users:

# Set default locale in /etc/default/locale
echo "LANG=nl_NL.UTF-8" | sudo tee /etc/default/locale
echo "LC_ALL=nl_NL.UTF-8" | sudo tee -a /etc/default/locale

# Alternative: User-specific configuration
echo "export LANG=nl_NL.UTF-8" >> ~/.bashrc
echo "export LC_ALL=nl_NL.UTF-8" >> ~/.bashrc
source ~/.bashrc

Verify your date formatting now works correctly:

date +"%A %d %B %Y"
# Should output Dutch date like "zaterdag 15 augustus 2009"

You might want to set specific locale categories separately:

LC_TIME=nl_NL.UTF-8  # Affects date/time formatting
LC_MONETARY=nl_NL.UTF-8  # Affects currency formatting
LC_NUMERIC=nl_NL.UTF-8  # Affects number formatting

If you still encounter problems:

# Check current locale settings
locale

# Verify locale files exist
ls /usr/share/locale/nl_NL/

# Check environment variables
printenv | grep LC_

---

When developing multilingual web applications, proper locale configuration is crucial for formatting dates, numbers, and other region-specific data. In your case, while your UI displays Dutch text, the system continues to output dates in English because the Dutch locale isn't properly installed or configured.

First, verify if the Dutch locale is actually installed on your Debian system:

locale -a | grep nl_NL

If this returns nothing, you'll need to install the locale package.

Run the following commands to install and generate the Dutch locale:

sudo apt-get update
sudo apt-get install locales
sudo dpkg-reconfigure locales

During configuration, scroll through the list and select nl_NL.UTF-8 (and optionally other Dutch variants). Set nl_NL.UTF-8 as the default system locale.

After installation, check if you can now use the Dutch locale:

LC_ALL=nl_NL.utf8 date

You should see output like:

za 15 aug 2009 14:31:36 UTC

For system-wide changes, edit /etc/default/locale:

LANG="nl_NL.UTF-8"
LC_ALL="nl_NL.UTF-8"

For user-specific changes, add these lines to your ~/.bashrc or ~/.profile.

If you still see English output:

• Verify the locale is properly generated (locale -a)
• Check if the locale is properly set (locale command)
• Ensure all locale-related packages are installed

For PHP applications, you can set the locale programmatically:

setlocale(LC_TIME, 'nl_NL.utf8');
echo strftime("%A %e %B %Y"); // Outputs Dutch date

For Python applications:

import locale
locale.setlocale(locale.LC_TIME, 'nl_NL.utf8')

If you can't modify system locales, consider implementing a translation layer in your application. Here's a simple PHP example:

$dateTranslations = [
    'Monday' => 'maandag',
    'January' => 'januari',
    // Add all necessary translations
];

$englishDate = date('l j F Y');
$dutchDate = strtr($englishDate, $dateTranslations);