Added: Add `ShellCommandShellEnvironment` and `TermuxShellCommandShellEnvironment` to export `ExecutionCommand` variables

This adds onto f102ea20 to build termux environment. Variables for `ExecutionCommand` app have the `SHELL_CMD__` scope. Docs will be provided for details of the variables.

- `SHELL_CMD__SHELL_ID`
- `SHELL_CMD__SHELL_NAME`
- `SHELL_CMD__APP_SHELL_NUMBER_SINCE_BOOT`
- `SHELL_CMD__TERMINAL_SESSION_NUMBER_SINCE_BOOT`
- `SHELL_CMD__APP_SHELL_NUMBER_SINCE_APP_START`
- `SHELL_CMD__TERMINAL_SESSION_NUMBER_SINCE_APP_START`

The commit also adds `SystemEventReceiver` to Termux app that will receive `ACTION_BOOT_COMPLETED`.

app/src/main/AndroidManifest.xml

@@ -34,6 +34,7 @@
     <uses-permission android:name="android.permission.DUMP" />
     <uses-permission android:name="android.permission.WRITE_SECURE_SETTINGS" />
     <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
+    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
     <uses-permission android:name="android.permission.PACKAGE_USAGE_STATS" tools:ignore="ProtectedPermissions" />
 
     <application
@@ -169,6 +170,14 @@
             android:name=".app.TermuxOpenReceiver"
             android:exported="false" />
 
+        <receiver
+            android:name=".app.event.SystemEventReceiver"
+            android:exported="false">
+            <intent-filter>
+                <action android:name="android.intent.action.BOOT_COMPLETED" />
+            </intent-filter>
+        </receiver>
+
         <receiver
             android:name=".shared.activities.ReportActivity$ReportActivityBroadcastReceiver"
             android:exported="false" />

app/src/main/java/com/termux/app/TermuxService.java

@@ -170,6 +170,8 @@ public final class TermuxService extends Service implements AppShell.AppShellCli
         actionReleaseWakeLock(false);
         if (!mWantsToStop)
             killAllTermuxExecutionCommands();
+
+        TermuxShellManager.onAppExit(this);
         runStopForeground();
     }
 
@@ -463,6 +465,8 @@ public final class TermuxService extends Service implements AppShell.AppShellCli
             return null;
         }
 
+        executionCommand.setShellCommandShellEnvironment = true;
+
         if (Logger.getLogLevel() >= Logger.LOG_LEVEL_VERBOSE)
             Logger.logVerboseExtended(LOG_TAG, executionCommand.toString());
 
@@ -571,13 +575,15 @@ public final class TermuxService extends Service implements AppShell.AppShellCli
             return null;
         }
 
+        executionCommand.setShellCommandShellEnvironment = true;
+        executionCommand.terminalTranscriptRows = mProperties.getTerminalTranscriptRows();
+
         if (Logger.getLogLevel() >= Logger.LOG_LEVEL_VERBOSE)
             Logger.logVerboseExtended(LOG_TAG, executionCommand.toString());
 
         // If the execution command was started for a plugin, only then will the stdout be set
         // Otherwise if command was manually started by the user like by adding a new terminal session,
         // then no need to set stdout
-        executionCommand.terminalTranscriptRows = mProperties.getTerminalTranscriptRows();
         TermuxSession newTermuxSession = TermuxSession.execute(this, executionCommand, getTermuxTerminalSessionClient(),
             this, new TermuxShellEnvironment(), null, executionCommand.isPluginExecutionCommand);
         if (newTermuxSession == null) {

app/src/main/java/com/termux/app/event/SystemEventReceiver.java

@@ -0,0 +1,47 @@
+package com.termux.app.event;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.termux.shared.data.IntentUtils;
+import com.termux.shared.logger.Logger;
+import com.termux.shared.termux.shell.TermuxShellManager;
+
+public class SystemEventReceiver extends BroadcastReceiver {
+
+    private static SystemEventReceiver mInstance;
+
+    private static final String LOG_TAG = "SystemEventReceiver";
+
+    public static synchronized SystemEventReceiver getInstance() {
+        if (mInstance == null) {
+            mInstance = new SystemEventReceiver();
+        }
+        return mInstance;
+    }
+
+    @Override
+    public void onReceive(@NonNull Context context, @Nullable Intent intent) {
+        if (intent == null) return;
+        Logger.logDebug(LOG_TAG, "Intent Received:\n" + IntentUtils.getIntentString(intent));
+
+        String action = intent.getAction();
+        if (action == null) return;
+
+        switch (action) {
+            case Intent.ACTION_BOOT_COMPLETED:
+                onActionBootCompleted(context, intent);
+                break;
+            default:
+                Logger.logError(LOG_TAG, "Invalid action \"" + action + "\" passed to " + LOG_TAG);
+        }
+    }
+
+    public synchronized void onActionBootCompleted(@NonNull Context context, @NonNull Intent intent) {
+        TermuxShellManager.onActionBootCompleted(context, intent);
+    }
+
+}

termux-shared/src/main/java/com/termux/shared/settings/preferences/SharedPreferenceUtils.java

@@ -188,6 +188,38 @@ public class SharedPreferenceUtils {
             sharedPreferences.edit().putInt(key, value).apply();
     }
 
+    /**
+     * Set an {@code int} in {@link SharedPreferences}.
+     *
+     * @param sharedPreferences The {@link SharedPreferences} to set the value in.
+     * @param key The key for the value.
+     * @param def The default value if failed to read a valid value.
+     * @param commitToFile If set to {@code true}, then value will be set to shared preferences
+     *                     in-memory cache and the file synchronously. Ideally, only to be used for
+     *                     multi-process use-cases.
+     * @param resetValue The value if not {@code null} that should be set if current or incremented
+     *                   value is less than 0.
+     * @return Returns the {@code int} value stored in {@link SharedPreferences} before increment,
+     * otherwise returns default if failed to read a valid value, like in case of an exception.
+     */
+    @SuppressLint("ApplySharedPref")
+    public static int getAndIncrementInt(SharedPreferences sharedPreferences, String key, int def,
+                                         boolean commitToFile, Integer resetValue) {
+        if (sharedPreferences == null) {
+            Logger.logError(LOG_TAG, "Ignoring incrementing int value for the \"" + key + "\" key into null shared preferences.");
+            return def;
+        }
+
+        int curValue = getInt(sharedPreferences, key, def);
+        if (resetValue != null && (curValue < 0)) curValue = resetValue;
+
+        int newValue = curValue + 1;
+        if (resetValue != null && newValue < 0) newValue = resetValue;
+
+        setInt(sharedPreferences, key, newValue, commitToFile);
+        return curValue;
+    }
+
 
 
     /**

termux-shared/src/main/java/com/termux/shared/shell/command/ExecutionCommand.java

@@ -195,6 +195,10 @@ public class ExecutionCommand {
     /** The {@link ShellCreateMode} of commands. */
     public String shellCreateMode;
 
+    /** Whether to set {@link ExecutionCommand} shell environment. */
+    public boolean setShellCommandShellEnvironment;
+
+
 
 
     /** The command label for the {@link ExecutionCommand}. */
@@ -396,6 +400,8 @@ public class ExecutionCommand {
             logString.append("\n").append(executionCommand.getShellCreateModeLogString());
         }
 
+        logString.append("\n").append(executionCommand.getSetRunnerShellEnvironmentLogString());
+
         if (!ignoreNull || executionCommand.commandIntent != null)
             logString.append("\n").append(executionCommand.getCommandIntentLogString());
 
@@ -490,7 +496,7 @@ public class ExecutionCommand {
 
         markdownString.append("\n").append(MarkdownUtils.getSingleLineMarkdownStringEntry("Shell Name", executionCommand.shellName, "-"));
         markdownString.append("\n").append(MarkdownUtils.getSingleLineMarkdownStringEntry("Shell Create Mode", executionCommand.shellCreateMode, "-"));
-
+        markdownString.append("\n").append(MarkdownUtils.getSingleLineMarkdownStringEntry("Set Shell Command Shell Environment", executionCommand.setShellCommandShellEnvironment, "-"));
 
         markdownString.append("\n").append(MarkdownUtils.getSingleLineMarkdownStringEntry("isPluginExecutionCommand", executionCommand.isPluginExecutionCommand, "-"));
 
@@ -588,6 +594,10 @@ public class ExecutionCommand {
         return Logger.getSingleLineLogStringEntry("Shell Create Mode", shellCreateMode, "-");
     }
 
+    public String getSetRunnerShellEnvironmentLogString() {
+        return "Set Shell Command Shell Environment: `" + setShellCommandShellEnvironment + "`";
+    }
+
     public String getCommandDescriptionLogString() {
         return Logger.getSingleLineLogStringEntry("Command Description", commandDescription, "-");
     }

termux-shared/src/main/java/com/termux/shared/shell/command/environment/AndroidShellEnvironment.java

@@ -20,6 +20,12 @@ import java.util.HashMap;
  */
 public class AndroidShellEnvironment extends UnixShellEnvironment {
 
+    protected ShellCommandShellEnvironment shellCommandShellEnvironment;
+
+    public AndroidShellEnvironment() {
+        shellCommandShellEnvironment = new ShellCommandShellEnvironment();
+    }
+
     /** Get shell environment for Android. */
     @NonNull
     @Override
@@ -85,6 +91,9 @@ public class AndroidShellEnvironment extends UnixShellEnvironment {
             getDefaultWorkingDirectoryPath());
         ShellEnvironmentUtils.createHomeDir(environment);
 
+        if (executionCommand.setShellCommandShellEnvironment && shellCommandShellEnvironment != null)
+            environment.putAll(shellCommandShellEnvironment.getEnvironment(currentPackageContext, executionCommand));
+
         return environment;
     }
 

termux-shared/src/main/java/com/termux/shared/shell/command/environment/ShellCommandShellEnvironment.java

@@ -0,0 +1,62 @@
+package com.termux.shared.shell.command.environment;
+
+import android.content.Context;
+
+import androidx.annotation.NonNull;
+
+import com.termux.shared.shell.command.ExecutionCommand;
+
+import java.util.HashMap;
+
+/**
+ * Environment for {@link ExecutionCommand}.
+ */
+public class ShellCommandShellEnvironment {
+
+    /** Environment variable prefix for the {@link ExecutionCommand}. */
+    public static final String SHELL_CMD_ENV_PREFIX = "SHELL_CMD__";
+
+    /** Environment variable for the {@link ExecutionCommand.Runner} name. */
+    public static final String ENV_SHELL_CMD__RUNNER_NAME = SHELL_CMD_ENV_PREFIX + "RUNNER_NAME";
+
+    /** Environment variable for the package name running the {@link ExecutionCommand}. */
+    public static final String ENV_SHELL_CMD__PACKAGE_NAME = SHELL_CMD_ENV_PREFIX + "PACKAGE_NAME";
+
+    /** Environment variable for the {@link ExecutionCommand#id}/TermuxShellManager.SHELL_ID name.
+     * This will be common for all runners. */
+    public static final String ENV_SHELL_CMD__SHELL_ID = SHELL_CMD_ENV_PREFIX + "SHELL_ID";
+
+    /** Environment variable for the {@link ExecutionCommand#shellName} name. */
+    public static final String ENV_SHELL_CMD__SHELL_NAME = SHELL_CMD_ENV_PREFIX + "SHELL_NAME";
+    
+    /** Environment variable for the {@link ExecutionCommand.Runner#APP_SHELL} number since boot. */
+    public static final String ENV_SHELL_CMD__APP_SHELL_NUMBER_SINCE_BOOT = SHELL_CMD_ENV_PREFIX + "APP_SHELL_NUMBER_SINCE_BOOT";
+
+    /** Environment variable for the {{@link ExecutionCommand.Runner#TERMINAL_SESSION} number since boot. */
+    public static final String ENV_SHELL_CMD__TERMINAL_SESSION_NUMBER_SINCE_BOOT = SHELL_CMD_ENV_PREFIX + "TERMINAL_SESSION_NUMBER_SINCE_BOOT";
+
+    /** Environment variable for the {@link ExecutionCommand.Runner#APP_SHELL} number since app start. */
+    public static final String ENV_SHELL_CMD__APP_SHELL_NUMBER_SINCE_APP_START = SHELL_CMD_ENV_PREFIX + "APP_SHELL_NUMBER_SINCE_APP_START";
+
+    /** Environment variable for the {@link ExecutionCommand.Runner#TERMINAL_SESSION} number since app start. */
+    public static final String ENV_SHELL_CMD__TERMINAL_SESSION_NUMBER_SINCE_APP_START = SHELL_CMD_ENV_PREFIX + "TERMINAL_SESSION_NUMBER_SINCE_APP_START";
+
+
+    /** Get shell environment containing info for {@link ExecutionCommand}. */
+    @NonNull
+    public HashMap<String, String> getEnvironment(@NonNull Context currentPackageContext,
+                                                  @NonNull ExecutionCommand executionCommand) {
+        HashMap<String, String> environment = new HashMap<>();
+
+        ExecutionCommand.Runner runner = ExecutionCommand.Runner.runnerOf(executionCommand.runner);
+        if (runner == null) return environment;
+
+        ShellEnvironmentUtils.putToEnvIfSet(environment, ENV_SHELL_CMD__RUNNER_NAME, runner.getName());
+        ShellEnvironmentUtils.putToEnvIfSet(environment, ENV_SHELL_CMD__PACKAGE_NAME, currentPackageContext.getPackageName());
+        ShellEnvironmentUtils.putToEnvIfSet(environment, ENV_SHELL_CMD__SHELL_ID, String.valueOf(executionCommand.id));
+        ShellEnvironmentUtils.putToEnvIfSet(environment, ENV_SHELL_CMD__SHELL_NAME, executionCommand.shellName);
+
+        return environment;
+    }
+
+}

termux-shared/src/main/java/com/termux/shared/termux/settings/preferences/TermuxAppSharedPreferences.java

@@ -215,6 +215,28 @@ public class TermuxAppSharedPreferences {
     }
 
 
+    public synchronized int getAndIncrementAppShellNumberSinceBoot() {
+        // Keep value at MAX_VALUE on integer overflow and not 0, since not first shell
+        return SharedPreferenceUtils.getAndIncrementInt(mSharedPreferences, TERMUX_APP.KEY_APP_SHELL_NUMBER_SINCE_BOOT,
+            TERMUX_APP.DEFAULT_VALUE_APP_SHELL_NUMBER_SINCE_BOOT, true, Integer.MAX_VALUE);
+    }
+
+    public synchronized void resetAppShellNumberSinceBoot() {
+        SharedPreferenceUtils.setInt(mSharedPreferences, TERMUX_APP.KEY_APP_SHELL_NUMBER_SINCE_BOOT,
+            TERMUX_APP.DEFAULT_VALUE_APP_SHELL_NUMBER_SINCE_BOOT, true);
+    }
+
+    public synchronized int getAndIncrementTerminalSessionNumberSinceBoot() {
+        // Keep value at MAX_VALUE on integer overflow and not 0, since not first shell
+        return SharedPreferenceUtils.getAndIncrementInt(mSharedPreferences, TERMUX_APP.KEY_TERMINAL_SESSION_NUMBER_SINCE_BOOT,
+            TERMUX_APP.DEFAULT_VALUE_TERMINAL_SESSION_NUMBER_SINCE_BOOT, true, Integer.MAX_VALUE);
+    }
+
+    public synchronized void resetTerminalSessionNumberSinceBoot() {
+        SharedPreferenceUtils.setInt(mSharedPreferences, TERMUX_APP.KEY_TERMINAL_SESSION_NUMBER_SINCE_BOOT,
+            TERMUX_APP.DEFAULT_VALUE_TERMINAL_SESSION_NUMBER_SINCE_BOOT, true);
+    }
+
 
     public boolean isTerminalViewKeyLoggingEnabled() {
         return SharedPreferenceUtils.getBoolean(mSharedPreferences, TERMUX_APP.KEY_TERMINAL_VIEW_KEY_LOGGING_ENABLED, TERMUX_APP.DEFAULT_VALUE_TERMINAL_VIEW_KEY_LOGGING_ENABLED);

termux-shared/src/main/java/com/termux/shared/termux/settings/preferences/TermuxPreferenceConstants.java

@@ -1,7 +1,7 @@
 package com.termux.shared.termux.settings.preferences;
 
 /*
- * Version: v0.15.0
+ * Version: v0.16.0
  *
  * Changelog
  *
@@ -65,8 +65,14 @@ package com.termux.shared.termux.settings.preferences;
  * - 0.15.0 (2021-09-05)
  *      - Added following to `TERMUX_TASKER_APP`:
  *          `KEY_LAST_PENDING_INTENT_REQUEST_CODE` and `DEFAULT_VALUE_KEY_LAST_PENDING_INTENT_REQUEST_CODE`.
+ *
+ * - 0.16.0 (2022-06-11)
+ *      - Added following to `TERMUX_APP`:
+ *          `KEY_APP_SHELL_NUMBER_SINCE_BOOT` and `KEY_TERMINAL_SESSION_NUMBER_SINCE_BOOT`.
  */
 
+import com.termux.shared.shell.command.ExecutionCommand;
+
 /**
  * A class that defines shared constants of the SharedPreferences used by Termux app and its plugins.
  * This class will be hosted by termux-shared lib and should be imported by other termux plugin
@@ -143,6 +149,18 @@ public final class TermuxPreferenceConstants {
         public static final String KEY_LAST_NOTIFICATION_ID = "last_notification_id";
         public static final int DEFAULT_VALUE_KEY_LAST_NOTIFICATION_ID = 0;
 
+        /**
+         * The {@link ExecutionCommand.Runner#APP_SHELL} number after termux app process since boot.
+         */
+        public static final String KEY_APP_SHELL_NUMBER_SINCE_BOOT = "app_shell_number_since_boot";
+        public static final int DEFAULT_VALUE_APP_SHELL_NUMBER_SINCE_BOOT = 0;
+
+        /**
+         * The {@link ExecutionCommand.Runner#TERMINAL_SESSION} number after termux app process since boot.
+         */
+        public static final String KEY_TERMINAL_SESSION_NUMBER_SINCE_BOOT = "terminal_session_number_since_boot";
+        public static final int DEFAULT_VALUE_TERMINAL_SESSION_NUMBER_SINCE_BOOT = 0;
+
 
         /**
          * Defines the key for whether termux terminal view key logging is enabled or not

termux-shared/src/main/java/com/termux/shared/termux/shell/TermuxShellManager.java

@@ -40,6 +40,16 @@ public class TermuxShellManager {
      */
     public final List<ExecutionCommand> mPendingPluginExecutionCommands = new ArrayList<>();
 
+    /**
+     * The {@link ExecutionCommand.Runner#APP_SHELL} number after app process was started/restarted.
+     */
+    public static int APP_SHELL_NUMBER_SINCE_APP_START;
+
+    /**
+     * The {@link ExecutionCommand.Runner#TERMINAL_SESSION} number after app process was started/restarted.
+     */
+    public static int TERMINAL_SESSION_NUMBER_SINCE_APP_START;
+
 
 
     public TermuxShellManager(@NonNull Context context) {
@@ -69,8 +79,45 @@ public class TermuxShellManager {
     }
 
 
+    public synchronized static void onActionBootCompleted(@NonNull Context context, @NonNull Intent intent) {
+        TermuxAppSharedPreferences preferences = TermuxAppSharedPreferences.build(context);
+        if (preferences == null) return;
+
+        // Ensure any shells started after boot have valid ENV_SHELL_CMD__APP_SHELL_NUMBER_SINCE_BOOT and
+        // ENV_SHELL_CMD__TERMINAL_SESSION_NUMBER_SINCE_BOOT exported
+        preferences.resetAppShellNumberSinceBoot();
+        preferences.resetTerminalSessionNumberSinceBoot();
+    }
+
+    public static void onAppExit(@NonNull Context context) {
+        // Ensure any shells started after boot have valid ENV_SHELL_CMD__APP_SHELL_NUMBER_SINCE_APP_START and
+        // ENV_SHELL_CMD__TERMINAL_SESSION_NUMBER_SINCE_APP_START exported
+        APP_SHELL_NUMBER_SINCE_APP_START = 0;
+        TERMINAL_SESSION_NUMBER_SINCE_APP_START = 0;
+    }
+
     public static synchronized int getNextShellId() {
         return SHELL_ID++;
     }
 
+    public static synchronized int getAndIncrementAppShellNumberSinceAppStart() {
+        // Keep value at MAX_VALUE on integer overflow and not 0, since not first shell
+        int curValue = APP_SHELL_NUMBER_SINCE_APP_START;
+        if (curValue < 0) curValue = Integer.MAX_VALUE;
+
+        APP_SHELL_NUMBER_SINCE_APP_START = curValue + 1;
+        if (APP_SHELL_NUMBER_SINCE_APP_START < 0) APP_SHELL_NUMBER_SINCE_APP_START = Integer.MAX_VALUE;
+        return curValue;
+    }
+
+    public static synchronized int getAndIncrementTerminalSessionNumberSinceAppStart() {
+        // Keep value at MAX_VALUE on integer overflow and not 0, since not first shell
+        int curValue = TERMINAL_SESSION_NUMBER_SINCE_APP_START;
+        if (curValue < 0) curValue = Integer.MAX_VALUE;
+
+        TERMINAL_SESSION_NUMBER_SINCE_APP_START = curValue + 1;
+        if (TERMINAL_SESSION_NUMBER_SINCE_APP_START < 0) TERMINAL_SESSION_NUMBER_SINCE_APP_START = Integer.MAX_VALUE;
+        return curValue;
+    }
+
 }

termux-shared/src/main/java/com/termux/shared/termux/shell/command/environment/TermuxShellCommandShellEnvironment.java

@@ -0,0 +1,48 @@
+package com.termux.shared.termux.shell.command.environment;
+
+import android.content.Context;
+
+import androidx.annotation.NonNull;
+
+import com.termux.shared.shell.command.ExecutionCommand;
+import com.termux.shared.shell.command.environment.ShellCommandShellEnvironment;
+import com.termux.shared.shell.command.environment.ShellEnvironmentUtils;
+import com.termux.shared.termux.settings.preferences.TermuxAppSharedPreferences;
+import com.termux.shared.termux.shell.TermuxShellManager;
+
+import java.util.HashMap;
+
+/**
+ * Environment for Termux {@link ExecutionCommand}.
+ */
+public class TermuxShellCommandShellEnvironment extends ShellCommandShellEnvironment {
+
+    /** Get shell environment containing info for Termux {@link ExecutionCommand}. */
+    @NonNull
+    @Override
+    public HashMap<String, String> getEnvironment(@NonNull Context currentPackageContext,
+                                                  @NonNull ExecutionCommand executionCommand) {
+        HashMap<String, String> environment = super.getEnvironment(currentPackageContext, executionCommand);
+
+        TermuxAppSharedPreferences preferences = TermuxAppSharedPreferences.build(currentPackageContext);
+        if (preferences == null) return environment;
+
+        if (ExecutionCommand.Runner.APP_SHELL.equalsRunner(executionCommand.runner)) {
+            ShellEnvironmentUtils.putToEnvIfSet(environment, ENV_SHELL_CMD__APP_SHELL_NUMBER_SINCE_BOOT,
+                String.valueOf(preferences.getAndIncrementAppShellNumberSinceBoot()));
+            ShellEnvironmentUtils.putToEnvIfSet(environment, ENV_SHELL_CMD__APP_SHELL_NUMBER_SINCE_APP_START,
+                String.valueOf(TermuxShellManager.getAndIncrementAppShellNumberSinceAppStart()));
+
+        } else if (ExecutionCommand.Runner.TERMINAL_SESSION.equalsRunner(executionCommand.runner)) {
+            ShellEnvironmentUtils.putToEnvIfSet(environment, ENV_SHELL_CMD__TERMINAL_SESSION_NUMBER_SINCE_BOOT,
+                String.valueOf(preferences.getAndIncrementTerminalSessionNumberSinceBoot()));
+            ShellEnvironmentUtils.putToEnvIfSet(environment, ENV_SHELL_CMD__TERMINAL_SESSION_NUMBER_SINCE_APP_START,
+                String.valueOf(TermuxShellManager.getAndIncrementTerminalSessionNumberSinceAppStart()));
+        } else {
+            return environment;
+        }
+
+        return environment;
+    }
+
+}

termux-shared/src/main/java/com/termux/shared/termux/shell/command/environment/TermuxShellEnvironment.java

@@ -23,6 +23,10 @@ public class TermuxShellEnvironment extends AndroidShellEnvironment {
     /** Environment variable for the termux {@link TermuxConstants#TERMUX_PREFIX_DIR_PATH}. */
     public static final String ENV_PREFIX = "PREFIX";
 
+    public TermuxShellEnvironment() {
+        super();
+        shellCommandShellEnvironment = new TermuxShellCommandShellEnvironment();
+    }
 
     /** Get shell environment for Termux. */
     @NonNull