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      wcscpy, wcscpy_s

      From cppreference.com
      <c‎ |string‎ |wide
       
       
       
      Null-terminated wide strings
       
      Defined in header<wchar.h>
      (1)
      wchar_t* wcscpy(wchar_t* dest,constwchar_t* src);
      		(since C95)
      (until C99)
      wchar_t* wcscpy(wchar_t*restrict dest,constwchar_t*restrict src);
      		(since C99)
      errno_t wcscpy_s(wchar_t*restrict dest, rsize_t destsz,
                       constwchar_t*restrict src);
      		 (2)(since C11)
      1) Copies the wide string pointed to bysrc (including the terminating null wide character) to wide character array pointed to bydest. The behavior is undefined if thedest array is not large enough. The behavior is undefined if the strings overlap.
      2) Same as(1), except that it may clobber the rest of the destination array with unspecified values and that the following errors are detected at runtime and call the currently installedconstraint handler function:
      • src ordest is a null pointer
      • destsz is zero or greater thanRSIZE_MAX/sizeof(wchar_t)
      • destsz is less or equalwcsnlen_s(src, destsz), in other words, truncation would occur
      • overlap would occur between the source and the destination strings
      As with all bounds-checked functions,wcscpy_s is only guaranteed to be available if__STDC_LIB_EXT1__ is defined by the implementation and if the user defines__STDC_WANT_LIB_EXT1__ to the integer constant1 before including<wchar.h>.

      Contents

      [edit]Parameters

      dest - pointer to the wide character array to copy to
      src - pointer to the null-terminated wide string to copy from
      destsz - maximum number of characters to write, typically the size of the destination buffer

      [edit]Return value

      1) returns a copy ofdest
      2) returns zero on success, returns non-zero on error. Also, on error, writesL'\0' todest[0] (unlessdest is a null pointer ordestsz is zero or greater thanRMAX_SIZE/sizeof(wchar_t)).

      [edit]Example

      Run this code
      #include <locale.h>#include <stdio.h>#include <wchar.h> int main(void){wchar_t* src= L"犬 means dog";//  src[0] = L'狗' ; // this would be undefined behaviorwchar_t dst[wcslen(src)+1];// +1 for the null terminator    wcscpy(dst, src);    dst[0]= L'狗';// OK setlocale(LC_ALL,"en_US.utf8");printf("src = %ls\ndst = %ls\n", src, dst);}

      Output:

      src = 犬 means dogdst = 狗 means dog

      [edit]References

      • C23 standard (ISO/IEC 9899:2024):
      • 7.29.4.1.2 The wcscpy function (p: TBD)
      • K.3.9.2.1.1 The wcscpy_s function (p: TBD)
      • C17 standard (ISO/IEC 9899:2018):
      • 7.29.4.1.2 The wcscpy function (p: TBD)
      • K.3.9.2.1.1 The wcscpy_s function (p: TBD)
      • C11 standard (ISO/IEC 9899:2011):
      • 7.29.4.1.2 The wcscpy function (p: 430)
      • K.3.9.2.1.1 The wcscpy_s function (p: 639)
      • C99 standard (ISO/IEC 9899:1999):
      • 7.24.4.1.2 The wcscpy function (p: 376)

      [edit]See also

      copies a certain amount of wide characters from one string to another
      (function)[edit]
      copies a certain amount of wide characters between two non-overlapping arrays
      (function)[edit]
      copies one string to another
      (function)[edit]
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=c/string/wide/wcscpy&oldid=162699"
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