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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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T
toascii()
Convert a character to a 7-bit ASCII value

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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        Get the size of a character device
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        Assert a break condition over a communications line
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        Compute the gamma function of a number
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        Get time-accounting information
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        Time-specification structure
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        Get the number of seconds and nanoseconds since a given epoch
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        Convert a timespec structure to nanoseconds
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        The number of seconds by which the local time zone is earlier than UTC
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        Structure that describes calendar time
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        Create a temporary file
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        Generate a unique string for use as a filename
      - toascii()
        Convert a character to a 7-bit ASCII value
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        Convert a character to lowercase
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        Convert a character to uppercase
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        Convert a wide character in a specified manner
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        Convert a wide character to lowercase
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        Convert a wide character to uppercase
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        Insert a trace event for the entry to a function
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        Insert a trace event for the exit from a function
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        Get the flag from the header of a trace event
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        Insert a trace event for the current address
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        Insert a user combine trace event
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        Insert a trace event of an arbitrary class and type with arbitrary data
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        Insert a user string trace event
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        Insert a user simple trace event
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        Insert a user string trace event, specifying a maximum string length
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        Insert a user string trace event, using a variable argument list
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        Control the tracing of kernel events
      - traceparser()
        Process trace data
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        Attach a callback to a trace event
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        Attach a callback to a range of events
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        Set the traceparser debug modes
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        Destroy a traceparser state structure
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        Get information about traceparser
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        Initialize the traceparser state information
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        Round to a truncated integer value
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        Set a thread-specific data value
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        Get a fully qualified pathname for a file
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        Get a fully qualified pathname for a file
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        The abbreviations for the time zone for standard and daylight savings time
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        Set the time according to the current time zone
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  - WPA Control Interface Reference
    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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QNX Hypervisor and QNX Hypervisor for Safety
The QNX Hypervisor and QNX Hypervisor for Safety products allow you to run multiple OSs on a target system so you can separate critical and non-critical functions, support a wide variety of applications, and reduce hardware costs.
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.

toascii()

QNX SDP8.0C Library ReferenceAPIDeveloper

Convert a character to a 7-bit ASCII value

Synopsis:

#include <ctype.h>

int toascii( int c );

Arguments:

c: The character that you want to convert.

Library:

libc

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

Description:

The toascii() function converts c to the 7‑bit ASCII range by masking off all but the low 7 bits.

Returns:

The corresponding 7-bit ASCII value for the provided character.

Classification:

ANSI, POSIX 1003.1


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: March 25, 2026