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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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C Library Reference
W
wcsncmp()
Compare two wide-character strings, up to a given length

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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      - wcrtomb()
        Convert a wide-character code to a character
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        Compare two wide-character strings, ignoring case
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        Concatenate two wide-character strings
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        Find the first occurrence of a wide character in a string
      - wcscmp()
        Compare two wide-character strings
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        Compare two wide-character strings, using the locale's collating sequence
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        Copy a wide-character string
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        Count the wide characters at the beginning of a string that aren't in a given character set
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        Format the time into a wide-character string
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        Compute the length of a wide-character string
      - wcsncasecmp()
        Compare two wide-character strings, ignoring case, up to a given length
      - wcsncat()
        Concatenate two wide-character strings, up to a maximum length
      - wcsncmp()
        Compare two wide-character strings, up to a given length
      - wcsncpy()
        Copy a wide-character string, to a maximum length
      - wcspbrk()
        Find the first wide character in a string that's in a given character set
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        Find the last occurrence of a wide character in a string
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        Convert a wide-character string into a multibyte character string (restartable)
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        Count the wide characters at the beginning of a string that are in a given character set
      - wcsstr()
        Find one wide-character string inside another
      - wcstod(), wcstof(), wcstold()
        Convert a wide-character string into a double, float, or long double
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        Convert a wide-character string into an integer
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        Break a wide-character string into tokens
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        Convert a wide-character string into a long integer
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        Convert a wide-character string into a multibyte character string
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        Convert a wide-character string into an unsigned long integer
      - wcsxfrm()
        Transform one wide-character string into another, to a given length
      - wctob()
        Convert a wide character to a single-byte code
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        Convert a wide character into a multibyte character
      - wctrans()
        Define a wide-character mapping
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        Define a wide-character class
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        Determine the number of column positions of a wide character
      - wmemchr()
        Locate the first occurrence of a wide character in a buffer
      - wmemcmp()
        Compare the wide characters in two buffers
      - wmemcpy()
        Copy wide characters from one buffer to another
      - wmemmove()
        Copy wide characters from one buffer to another
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        Set wide characters in memory
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        Perform word expansions
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        Free a word expansion buffer
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        Write formatted output to stdout
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        Scan formatted wide-character input from stdin
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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.

wcsncmp()

QNX SDP8.0C Library ReferenceAPIDeveloper

Compare two wide-character strings, up to a given length

Synopsis:

#include <wchar.h>

int wcsncmp( const wchar_t * ws1,
             const wchar_t * ws2,
             size_t n );

Arguments:

ws1, ws2: The wide-character strings that you want to compare.
n: The maximum number of wide characters that you want to compare.

Library:

libc

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

Description:

The wcsncmp() function compares up n wide characters from the strings pointed to by ws1 and ws2.

Returns:

< 0: ws1 is less than ws2.
0: ws1 is equal to ws2.
> 0: ws1 is greater than ws2.

Classification:

ANSI, POSIX 1003.1


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: August 11, 2025