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T
towctrans()
Convert a wide character in a specified manner

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.
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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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      - towctrans()
        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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Typographical Conventions, Support, and Licensing
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towctrans()

QNX SDP8.0C Library ReferenceAPIDeveloper

Convert a wide character in a specified manner

Synopsis:

#include <wctype.h>

wint_t towctrans( wint_t wc,
                  wctrans_t category );

Arguments:

wc: The wide character that you want to convert.
category: How you want to convert the character; get this by calling wctrans().

Library:

libc

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

Description:

The towctrans() function converts wc, using the mapping described by category. The following functions are equivalent:


Function	Equivalent wctrans() call
`towlower(` `wc` `)`	`towctrans(` `wc, wctrans("tolower") )`
`towupper(` `wc` `)`	`towctrans(` `wc, wctrans("toupper") )`

Returns:

The corresponding converted wide character when the argument is valid; otherwise, the original wide character.

Classification:

ANSI, POSIX 1003.1


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: August 11, 2025