* maintained with a doubly linked list through the entries. All optional operations (put and
 * remove) are supported. Null keys and values are supported.
 *
 * <p>{@code containsKey(k)}, {@code put(k, v)} and {@code remove(k)} are all (expected and
 * amortized) constant time operations. Expected in the hashtable sense (depends on the hash

An <a href="https://en.wikipedia.org/wiki/Environment_variable" class="external-link" target="_blank">environment variable</a> (also known as "env var") is a variable that lives outside of the Python code, in the operating system, and could be read by your Python code (or by other programs as well).

You can create and use environment variables in the shell, without needing Python:

=== "Linux, macOS, Windows Bash"

    <div class="termy">

elif [[ ${LOCAL_ARCH} == ppc64le ]]; then
    TARGET_ARCH=ppc64le
else
    echo "This system's architecture, ${LOCAL_ARCH}, isn't supported"
    exit 1
fi

LOCAL_OS=$(uname)

# Pass environment set target operating-system to build system
if [[ ${TARGET_OS} ]]; then
    # Target explicitly set
    :
elif [[ $LOCAL_OS == Linux ]]; then
    TARGET_OS=linux
    readlink_flags="-f"
elif [[ $LOCAL_OS == Darwin ]]; then

* MinIO doesn't currently support PFX certificates.

### 3.1 Use `certgen` to Generate a Certificate

Download [`certgen`](https://github.com/minio/certgen/releases/latest) for your specific operating system and platform.

`certgen` is a simple *Go* tool to generate self-signed certificates, and provides SAN certificates with DNS and IP entries:

```sh
./certgen -host "10.10.0.3,10.10.0.4,10.10.0.5"
```

#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
#       see the in-line comments for details.
#
#       There are tweaks for specific operating systems such as AIX, CygWin,
#       Darwin, MinGW, and NonStop.
#
#   (3) This script is generated from the Groovy template

        </field>
      </fields>
    </class>
    <class>
      <name>ActivationOS</name>
      <version>1.0.0</version>
      <description><![CDATA[
        This is an activator which will detect an operating system's attributes in order to activate
        its profile.
      ]]></description>
      <fields>
        <field>
          <name>name</name>
          <version>1.0.0</version>
          <type>String</type>

// encoding. Unlike octal encoding, base-256 encoding does not require that the
// string ends with a NUL character. Thus, all n bytes are available for output.
//
// If operating in binary mode, this assumes strict GNU binary mode; which means
// that the first byte can only be either 0x80 or 0xff. Thus, the first byte is
// equivalent to the sign bit in two's complement form.

  }

  /**
   * An object that joins map entries in the same manner as {@code Joiner} joins iterables and
   * arrays. Like {@code Joiner}, it is thread-safe and immutable.
   *
   * <p>In addition to operating on {@code Map} instances, {@code MapJoiner} can operate on {@code
   * Multimap} entries in two distinct modes:
   *
   * <ul>

  }

  /**
   * An object that joins map entries in the same manner as {@code Joiner} joins iterables and
   * arrays. Like {@code Joiner}, it is thread-safe and immutable.
   *
   * <p>In addition to operating on {@code Map} instances, {@code MapJoiner} can operate on {@code
   * Multimap} entries in two distinct modes:
   *
   * <ul>

Your code needs to run on [all versions of Java that Gradle supports](platforms/documentation/docs/src/docs/userguide/releases/compatibility.adoc) and across all supported operating systems (macOS, Windows, Linux). The [Gradle CI system](http://builds.gradle.org/) will verify this, but here are some pointers that will avoid surprises: