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# NSBeginCriticalAlertSheet

Creates and runs a critical alert sheet.

```
extern void NSBeginCriticalAlertSheet(NSString *title, NSString *defaultButton, NSString *alternateButton, NSString *otherButton, NSWindow *docWindow, id modalDelegate, SEL didEndSelector, SEL didDismissSelector, void *contextInfo, NSString *msgFormat, ...);
```

## Discussion

Creates and runs a critical alert sheet on `docWindow`, with the title of `title`, the text of `msg`, and buttons with titles of `defaultButton`, `alternateButton`, and `otherButton`.

See the description of [`NSBeginAlertSheet`](/documentation/AppKit/NSBeginAlertSheet) for information on layout, default parameters, and the selectors.

The sheet presented to the user is badged with a caution icon. Critical alerts should be used only as specified in the “Alerts” section of the UI Element Guidelines: Windows chapter of [macOS Human Interface Guidelines](https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/OSXHIGuidelines/index.html#//apple_ref/doc/uid/20000957).

---

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