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rsrcdbmgr_devno_detach()
Detach a major and minor number

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.
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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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        Get major and minor device numbers
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        Detach a major and minor number
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rsrcdbmgr_devno_detach()

QNX SDP8.0C Library ReferenceAPIDeveloper

Detach a major and minor number

Synopsis:

#include <sys/rsrcdbmgr.h>

int rsrcdbmgr_devno_detach( dev_t devno,
                            int flags );

Arguments:

devno: A dev_t object that was returned by rsrcdbmgr_devno_attach().
flags: Presently, there are no flags; pass zero for this argument.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The rsrcdbmgr_devno_detach() function detaches a device number that was attached with rsrcdbmgr_devno_attach(). The process that's detaching the device number must be the process that attached it.

Note:

In order to successfully use the rsrcdbmgr_*() functions to modify the resource database, your process must have the PROCMGR_AID_RSRCDBMGR ability enabled. For more information, see procmgr_ability().

If you don't detach a device, it's released when the process that attached it terminates.

Returns:

EOK: Success.
-1: An error occurred (errno is set).

Errors:

EINTR

The call was interrupted by a signal.

EINVAL

One of the following occurred:

The major or minor device number in devno is invalid.
The device identified by devno isn't registered.
The calling process isn't the process that attached the device number.

EPERM

The calling process doesn't have the required permission; see procmgr_ability().

Examples:

#include <sys/rsrcdbmgr.h>

dev_t   dev_num;
int     flags=0;

…

rsrcdbmgr_devno_detach( dev_num, flags );

Classification:


Safety:
Cancellation point	Yes
Signal handler	Yes
Thread	Yes

Page updated: August 11, 2025