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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.
Utilities & Libraries
Devctl and Ioctl Commands
DCMD_PROF_*
DCMD_PROF_QUERY
Query if a capability is needed

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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    - BIOC*
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    - DCMD_PROF_*
      - DCMD_PROF_ATTACH
        Attach a process to the profiler
      - DCMD_PROF_DETACH
        Detach a process from the profiler
      - DCMD_PROF_MAPPING_ADD
        Add a mapping from a running process
      - DCMD_PROF_MAPPING_REM
        Remove a mapping from a running process
      - DCMD_PROF_QUERY
        Query if a capability is needed
    - DCMD_PTPD_*
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    This document provides a reference for the Wi-Fi Protected Access (WPA) control interface, which provides a C API for the WPA/IEEE 802.11i protocols in Wi-Fi client stations. Application developers who want to control WPA operations and get associated status and event data should read this reference.
- Migrating to QNX OS 8.0
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QNX Toolkit for Visual Studio Code
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This User's Guide explains the QNX hypervisor architecture and provides instructions for installing and running a QNX Hypervisor system, changing system components and configuration, and using hypervisor features such as virtual devices (vdevs).
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.

DCMD_PROF_QUERY

QNX SDP8.0Devctl and Ioctl CommandsDeveloper

Query if a capability is needed

Synopsis:

#include <sys/dcmd_prof.h>

#define DCMD_PROF_QUERY           __DIOT(_DCMD_MISC, PROF_QUERY, struct __prof_clientinfo)

Arguments to devctl():


Argument	Value
`filedes`	A file descriptor for the profiler that you obtained by opening /dev/profiler.
`dcmd`	DCMD_PROF_QUERY
`dev_data_ptr`	A pointer to a struct __prof_clientinfo (see DCMD_PROF_ATTACH)
`n_bytes`	`sizeof(struct __prof_clientinfo)`
`dev_info_ptr`	NULL

Description:

This command queries if a capability is needed, returning either EOK or EACCES.

Input:

Set the cmd member of the struct __prof_clientinfo to one of the following:

PROF_CMD_QUERY_THREAD — keep track of thread-level profiling information.
PROF_CMD_QUERY_SHLIB — try to profile shared libraries.

Output:

None.

Errors:

The devctl() function can return the following, in addition to the error codes listed in its entry in the C Library Reference:

EACCES: The capability isn't needed.

See also:

devctl() in the QNX OS C Library Reference

Page updated: March 05, 2025