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QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
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Utilities Reference
U
umount
Unmount a device

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX Tool Suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
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      - ubus_ctrl
        USB Bus State Enable/Disable utility
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        Micro-embedded shell (QNX OS)
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        Control a USB DCD link
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        Get or set the file mode creation mask (POSIX)
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        Unmount a device
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This User's Guide describes the QNX^® Toolkit for Visual Studio Code. The guide introduces you to the QNX Toolkit by explaining the QNX development environment and how to build, run, and debug your QNX^® Operating System (OS) applications and systems.
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation, explains how to obtain technical support, and provides some information about licensing.

umount

QNX SDP8.0Utilities ReferenceUtilities

Unmount a device

Syntax:

umount [-fv] [-T type] path [path ...]

Runs on:

QNX OS

Options:

-f: Force an unmount, even if the device is busy.
-T type: Typed umount (not currently supported).
-v: Be verbose.
path: The root mountpoint to be unmounted.

Description:

This utility unmounts the devices that were mounted as the given paths.

If a device is busy (for example, if a file is open), umount fails. You can force the device to be unmounted by specifying the -f option.

In order to use this utility, your process needs to have the vfs/mount-blk (BLK_ABILITY_MOUNTVFS) custom ability enabled. For more information, see procmgr_ability() and procmgr_ability_lookup() in the C Library Reference.

Page updated: August 09, 2024