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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: Embedded Python uncatchable hard exit on closing last matplotlib window.","articleBody":"### Bug summary\n\nOn macOS, default backend (Cocoa?), with Python embedded into an application, closing the last open Matplotlib window causes an uncatchable exit.  It does not throw a system exit exception to call Python's system exit, but rather a C level exit which causes the entire application to close.  This is fine if you are running Matplotlib from an interactive console, it is not fine when Python is embedded as a scripting language within an application.  \n\n### Code for reproduction\n\n```python\n# Embed Python into a minimal application, run application \r\n# from the embedded python scripting, run the script.\r\n# Such as running through PyRun_SimpleString(\"code\");  (not an interactive shell)\r\n\r\nimport matplotlib.pyplot as plt\r\nplt.clf()         # make sure we are starting with a clean plot\r\nplt.plot([1, 2, 3, 4])\r\nplt.ylabel('some numbers')\r\nplt.show()\r\n\r\n# close the window - application exits in an uncatchable manner.\n```\n\n\n### Actual outcome\n\nApplication shutdown that is not catchable.\n\n### Expected outcome\n\nWindow closes and script stops running and control is returned to interpreter, but Application with Python interpreter continues running.  Backend returns to a state waiting for another plot / window to be opened.\n\n### Additional information\n\nUse Matplotlib from an application that embeds Python as a scripting language.  Close last Matplotlib window.  Matplotlib forces application to close ungracefully, no way to catch close, no way to save / close opened files no way for an orderly shutdown and a C level exit is called.\r\n\r\nMatplotlib always forces exit for every version tried.\r\nWhy: A call to exit() or exit_() at the C level of the code, not a Python SystemExit.\r\nFix: Don't terminate the application with an uncatchable exit.\n\n### Operating system\n\nmacOS\n\n### Matplotlib Version\n\n3.8.0 and prior\n\n### Matplotlib Backend\n\nMacOSX\n\n### Python version\n\n3.11.5 ( and earlier all the way back to 3.5)\n\n### Jupyter version\n\n_No response_\n\n### Installation\n\npip","author":{"url":"https://github.com/prniii","@type":"Person","name":"prniii"},"datePublished":"2023-10-19T14:15:08.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":14},"url":"https://github.com/27147/matplotlib/issues/27147"}