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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
tcgetsize()
Get the size of a character 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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      - tan(), tanf(), tanl()
        Calculate the tangent of an angle
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        Calculate the hyperbolic tangent
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        Wait until all output has been transmitted to a device
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        Disconnect a communications line
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        Perform a flow-control operation on a data stream
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        Flush the input and/or output stream
      - tcgetattr()
        Get the current terminal control settings
      - tcgetpgrp()
        Get the process group ID associated with a device
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        Get the process group ID of the session leader for a controlling terminal
      - tcgetsize()
        Get the size of a character device
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        Inject characters into a device's input buffer
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        Determine the number of characters waiting to be read
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        Assert a break condition over a communications line
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        Change the terminal control settings for a device
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        Set the process group ID for a device
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        Make a terminal device a controlling device
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        Set the size of a character device
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        Get the location associated with the directory stream
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        Create a name for a temporary file
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        Terminal control structure
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        Compute the gamma function of a number
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        Create a thread
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        Get the calling thread's ID
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        Detach a thread from a process
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        Compare two thread IDs
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        Terminate a thread
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        Join thread
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        Make a thread sleep
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        Start a thread pool
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        Determine the current calendar time
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        Create a timer
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        Delete a timer
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        Get the expiry status of a timer
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        Return the number of timer overruns
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        Get the amount of time left on a timer
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        Arm a timer with the given expiration time, disarm it, or set its tolerance
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        Destroy a process timer
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        Get information about a timer
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        Arm a timer with the given expiration time, disarm it, or set its tolerance
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        Set a timeout on a blocking state
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        Get time-accounting information
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        Time-specification structure
      - timespec_get()
        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
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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
      - TraceEvent()
        Control the tracing of kernel events
      - traceparser()
        Process trace data
      - traceparser_cs()
        Attach a callback to a trace event
      - traceparser_cs_range()
        Attach a callback to a range of events
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        Set the traceparser debug modes
      - traceparser_destroy()
        Destroy a traceparser state structure
      - traceparser_get_info()
        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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        Truncate a file to a specified length
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        Create a thread-specific storage key
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        Delete thread-specific storage
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        Get a thread-specific data value
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        Set a thread-specific data value
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        Get a fully qualified pathname for a file
      - ttyname_r()
        Get a fully qualified pathname for a file
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        The abbreviations for the time zone for standard and daylight savings time
      - tzset()
        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 User's Guide
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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.

tcgetsize()

QNX SDP8.0C Library ReferenceAPIDeveloper

Get the size of a character device

Synopsis:

#include <termios.h>

int tcgetsize( int filedes,
               int* prows,
               int* pcols );

Arguments:

filedes: A file descriptor that's associated with the device whose size you want to get.
prows, pcols: NULL, or pointers to locations where the function can store the number of rows and columns.

Library:

libc

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

Description:

The tcgetsize() function gets the size of the character device associated with filedes and stores the number of rows and columns in prows and pcols if they're not NULL.

Returns:

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

Errors:

EACCES: The filedes argument isn't associated with a controlling terminal.
EBADF: The filedes argument isn't a valid file descriptor.
ENOTTY: The file associated with filedes isn't a terminal.

Classification:


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: August 11, 2025