Introduction

The Console Window, also called a Terminal, is an operating system text window that displays messages about Blender’s operations, status, and internal errors.

Use Cases:

  • For automation and batch processing which require launching Blender with different arguments.

  • For Python development, to see the output of the print() command.

  • If Blender exits unexpectedly, the messages may indicate the cause or error.

  • When troubleshooting, to see the output of --debug messages.

Platform Dependent Instructions

Linux

The Blender Console Window in Linux will typically only be visible on the desktop if Blender is manually started from a terminal. Blender outputs to the Console Window it is started from.

Depending on your desktop environment setup, a Blender icon may appear on your desktop or an entry for Blender is added to your menu after you install Blender. Often you can edit such an icon and enable “Run in terminal”.

../../_images/advanced_command-line_introduction_kde.png

Configuring the KDE menu icon to start Blender from a terminal.

This screenshot shows Blender started from a Linux Terminal and the resulting text output written to it:

../../_images/advanced_command-line_introduction_linux.png

Starting Blender from a Linux terminal window.

Apple macOS

macOS uses “files” with the .app extension called applications. These files are actually folders that appear as files in Finder. In order to run Blender you will have to specify that path to the Blender executable inside this folder, to get all output printed to the terminal. You can start a terminal from Applications ‣ Utilities. The path to the executable in the .app folder is ./blender.app/Contents/MacOS/blender.

If you have Blender installed in the Applications folder, the following command can be used:

/Applications/blender-2.80/blender.app/Contents/MacOS/blender
../../_images/advanced_command-line_introduction_mac.png

Starting Blender from a macOS console window.

Microsoft Windows

When Blender is started on a Microsoft Windows operating system, the Console Window (called the Command Prompt) is first created as a separate window on the desktop. The main Blender window will also appear and the Console Window will then be toggled off. To display the console again, go to Window ‣ Toggle System Console.

To start Blender from the command line you need to open an instance of Command Prompt. To do this, type WinKey-R then type cmd; this will open the Command Prompt window. You then need to find the path to the Blender executable. If you installed Blender via the installer then it can be found here:

C:\Program Files\Blender Foundation\Blender\blender.exe
../../_images/advanced_command-line_introduction_windows.png

Blender’s Console Window on Microsoft Windows.

The screenshot shows the Blender Console Window on Microsoft Windows directly after starting Blender and then a short while later after opening a file along with the relevant messages.

Tip

Closing the Blender Console Window

Closing the Console Window will also close Blender, losing any unsaved work.

To turn off the console without closing Blender, just run Toggle System Console again from the menu (as mentioned above).

Console Window Status and Error Messages

The Blender Console Window can display many different types of status and error messages. Some messages simply inform the user what Blender is doing, but have no real impact on Blender’s ability to function. Other messages can indicate serious errors that will most likely prevent Blender carrying out a particular task and may even make Blender non-responsive or shut down completely. The Blender Console Window messages can also originate internally from within the Blender code or from external sources such as Python scripts.

Common Messages

  • found bundled python: (FOLDER)

    This message indicates that Blender was able to find the Python library for the Python interpreter embedded within Blender. If this folder is missing or unable to be found, it is likely that an error will occur, and this message will not appear.

  • malloc returns nil()

    When Blender carries out operations that require extra memory (RAM), it calls a function called malloc (short for memory allocate) which tries to allocate a requested amount of memory for Blender. If this cannot be satisfied, malloc will return nil/null/0 to indicate that it failed to carry out the request. If this happens Blender will not be able to carry out the operation requested by the user. This will most likely result in Blender operating very slowly or shutting down. If you want to avoid running out of memory you can install more memory in your system, reduce the amount of detail in your Blender models, or shut down other programs and services which may be taking up memory that Blender could use.