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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
C Library Reference
W
wcwidth()
Determine the number of column positions of a wide character

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
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        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
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        Compare two wide-character strings, ignoring case, up to a given length
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        Concatenate two wide-character strings, up to a maximum length
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        Compare two wide-character strings, up to a given length
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        Copy a wide-character string, to a maximum length
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        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
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        Find one wide-character string inside another
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        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
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        Transform one wide-character string into another, to a given length
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        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
      - wctype()
        Define a wide-character class
      - wcwidth()
        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
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        Copy wide characters from one buffer to another
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        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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        Scan formatted wide-character input from stdin
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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.

wcwidth()

QNX SDP8.0C Library ReferenceAPIDeveloper

Determine the number of column positions of a wide character

Synopsis:

#include <wchar.h>

int wcwidth( const wchar_t wc );

Arguments:

wc: The code of the wide character whose width you want to determine

Library:

libc

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

Description:

The wcwidth() function determines the number of column positions required to represent the wide character wc.

Returns:

If wc is a printable wide-character, the value is at least 0. If wc is a NUL-terminating wide-character (L'\0'), the value is 0. Otherwise, -1 is returned.

Classification:

ANSI, POSIX 1003.1


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: August 09, 2024