How to strncpy() to WCHAR

Question

I got a piece of code that works under Multi-Byte Character Set. However, I want to convert this piece of code to UNICODE. So I fixed lots of stuff, but failed at the strncpy() line. This is the line that I want to change:

strncpy(a.szTip, szToolTip, bLength);

I used lots of functions to fix this, but all of them failed.

Here's the error:

strncpy cannot convert parameter 1 from WCHAR[128] to char *

strncpy() will copy bytes until it finds a byte with the value 0 (or reaches the specified maximum number of bytes), and then stop copying. So even if you cast the parameters to force it to compile, it probably wouldn't do what you want -- in particular, any multi-byte character that contained a zero for one of its bytes would cause strncpy() not to copy the remainder of the string. Perhaps you want to use wstrncpy() instead? — Jeremy Friesner, Sep 06 '12 at 16:13

Michael Foukarakis · Answer 1 · 2012-09-06T19:58:10.447

8

When dealing with wide characters, use wcsncpy() (and other relevant functions).

As Remy Lebeau points out, using the _tcsncpy() macro is safer if you want to support both ANSI & Unicode builds (it expands to the right function respectively).

edited Sep 06 '12 at 19:58

answered Sep 06 '12 at 16:13

Michael Foukarakis

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when dealing with Win32 API `TCHAR` values (which `szTip` is), use `_tcsncpy()` or `wsprintf()` instead. – Remy Lebeau Sep 06 '12 at 19:41
Ah, I wasn't aware what `szTip` was. Thanks. – Michael Foukarakis Sep 06 '12 at 19:58

How to strncpy() to WCHAR

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