How to use the command 'dex' (with examples)

The dex command, an abbreviation for DesktopEntry Execution, is a powerful tool that allows users to manage and execute DesktopEntry files of the Application type. These files, commonly used in Linux, are shortcuts that define how applications are launched. By leveraging dex, users can automate the execution of programs during system startup or manage them individually. This can be particularly useful for streamlining workflows and ensuring that essential applications start with the system without manual intervention.

Use case 1: Execute all programs in the autostart folders

Code:

dex --autostart

Motivation:

The motivation behind using this command is to automate the launch of all programs meant to start with the system, without individually executing each application. By doing so, users can save time and ensure that their workflow is immediately accessible upon logging into their system.

Explanation:

• --autostart: This flag directs dex to look into the autostart directories, primarily ~/.config/autostart or /etc/xdg/autostart, and execute all DesktopEntry files it finds. These are locations where applications place their startup entries, and executing them ensures that configured applications start automatically.

Example output:

Executing /home/user/.config/autostart/dropbox.desktop
Executing /home/user/.config/autostart/slack.desktop

Use case 2: Execute all programs in the specified folders

Code:

dex --autostart --search-paths path/to/directory1:path/to/directory2:path/to/directory3:

Motivation:

Sometimes, users might have additional directories with custom or departmental startup applications outside the default autostart directories. This command allows users to specify such directories and execute all programs within them. It’s particularly useful in corporate environments where specialized software needs launching as the system starts.

Explanation:

• --autostart: Activates the autostart functionality.
• --search-paths path/to/directory1:path/to/directory2:path/to/directory3:: Specifies custom directories, separated by a colon, to search for DesktopEntry files for execution.

Example output:

Executing /custom/directory1/example.desktop
Executing /custom/directory2/another-example.desktop

Use case 3: Preview the programs would be executed in a GNOME specific autostart

Code:

dex --autostart --environment GNOME

Motivation:

This command is beneficial for GNOME desktop users to preview what applications are set to launch when they log in. It helps in managing and verifying startup entries specific to the GNOME environment without actually executing them, thus providing a chance to make necessary adjustments beforehand.

Explanation:

• --autostart: Enables checking of autostart entries.
• --environment GNOME: Limits the output to entries relevant to the GNOME desktop environment, which might have specific requirements or configurations.

Example output:

[Preview] GNOME-specific application 1
[Preview] GNOME-specific application 2

Use case 4: Preview the programs would be executed in a regular autostart

Code:

dex --autostart --dry-run

Motivation:

The --dry-run option is ideal for users who want to see what programs will be launched on system startup without actually executing them. This command serves as a diagnostic tool to review all intended startup programs and address potential conflicts or unnecessary entries.

Explanation:

• --autostart: Tells dex to consider autostart entries.
• --dry-run: Prevents actual execution of programs, printing what would have been executed instead.

Example output:

[Preview] /home/user/.config/autostart/music-player.desktop
[Preview] /home/user/.config/autostart/news-app.desktop

Use case 5: Preview the value of the DesktopEntry property Name

Code:

dex --property Name path/to/file.desktop

Motivation:

For users intending to organize DesktopEntry files or verify an application’s entry name, this command provides a straightforward way to extract and view the specific Name property. It’s a useful feature for scripting or when modifying entries for clarity.

Explanation:

• --property Name: Requests the specific value of the Name property from a DesktopEntry file.
• path/to/file.desktop: Specifies the path to the DesktopEntry file from which the Name property is to be extracted.

Example output:

Name=Example Application

Use case 6: Create a DesktopEntry for a program in the current directory

Code:

dex --create path/to/file.desktop

Motivation:

Creating new DesktopEntry files is beneficial for adding shortcuts to new applications, scripts, or executables that do not automatically provide these entries upon installation. This command assists users in creating these entries, thus facilitating easier access and management of applications.

Explanation:

• --create: Initiates the creation process of a new DesktopEntry file.
• path/to/file.desktop: Indicates where the new DesktopEntry file will be created and stored.

Example output:

DesktopEntry created at /home/user/.local/share/applications/example.desktop

Use case 7: Execute a single program (with Terminal=true in the desktop file) in the given terminal

Code:

dex --term terminal path/to/file.desktop

Motivation:

Different applications may require being run within a specific terminal configuration, as dictated by the Terminal=true property. This command ensures that such programs are executed in the appropriate terminal application, making it pivotal for users who rely on terminal-based programs or scripts.

Explanation:

• --term terminal: Specifies the terminal emulator to use for executing the program (e.g., gnome-terminal, xterm).
• path/to/file.desktop: Denotes the path to the DesktopEntry file to be executed, where Terminal=true indicates the necessity of a terminal for execution.

Example output:

Launching /usr/bin/custom-terminal for /path/to/terminal-app.desktop

Conclusion:

The dex command is a versatile tool for managing DesktopEntry files, offering functionality that ranges from automated execution of startup programs to detailed previews and DesktopEntry creation. These use cases demonstrate its capacity to streamline workflows, provide control over application startup behavior, and aid in system management for both casual and power users.