wcsncat(3) Library Functions Manual wcsncat(3)
NAME
wcsncat, wcsncmp, wcsncpy - Perform operations on wide-character strings with a character count
LIBRARY
Standard C Library (libc)
SYNOPSIS
#include <wchar.h>
wchar_t *wcsncat(
wchar_t *wcstring1,
const wchar_t *wcstring2,
size_t number);
int wcsncmp(
const wchar_t *wcstring1,
const wchar_t *wcstring2,
size_t number);
wchar_t *wcsncpy(
wchar_t *wcstring1,
const wchar_t *wcstring2,
size_t number);
STANDARDS
Interfaces documented on this reference page conform to industry standards as follows:
wcsncat(), wcsncmp(), wcsncpy(): XSH5.0
Refer to the standards(5) reference page for more information about industry standards and associated tags.
PARAMETERS
Points to a location containing the first wide-character string. Points to a location containing the second wide-character string. Speci-
fies the number of wide characters in the string operation. In wcsncat(), specifies the maximum number of wide characters to append; in
wcsncmp(), specifies the maximum number of wide characters to compare; and, in wcsncpy, specifies the number of wide characters to copy.
DESCRIPTION
The wcsncat(), wcsncmp(), and wcsncpy() functions operate on null-terminated, wide-character strings.
The wcsncat() function appends wide characters from the wcstring2 parameter to the end of the wcstring1 parameter. The initial character
of the wcstring2 parameter overwrites the terminating null wide character of the wcstring1 parameter. The wcsncat() function appends char-
acters until it encounters a null wide character in wcstring2 or appends, at most, the number of characters specified by the value of the
number parameter. The function then appends a null wide character to the result and returns wcstring1. When operating on strings stored
in fields that overlap, the behavior of this function is unreliable.
The wcsncmp() function compares the wide characters in the wcstring1 parameter to the wcstring2 parameter. The wcsncmp() function compares
wide characters until it has compared number wide characters or until it has reached a terminating null wide character. The function com-
pares, at most, the number of wide characters specified by the value of the number parameter. When operating on strings stored in fields
that overlap, the behavior of this function is unreliable.
The wcsncmp() function compares strings based on the machine collating order. It does not use the locale-dependent sorting order. Use the
wcscoll() function for locale-dependent sorting.
The wcsncpy() function copies wide characters from the wcstring2 parameter to the wcstring1 parameter and returns wcstring1. The function
copies the number of wide characters specified by the value of the number parameter. If wcstring2 is shorter than number characters,
wcstring1 is padded out to number characters with null wide characters. However, if there is no null wide character in the first number
characters of the wcstring2 array, the result in the wcstring1 array is not null terminated.
RETURN VALUES
On successful completion, the wcsncat() and wcsncpy() functions return a pointer to the resulting string, wcstring1.
On successful completion, the wcsncmp() function returns an integer whose value is greater than 0 (zero) if wcstring1 is greater than
wcstring2, returns 0 (zero) if the strings are equivalent, and returns an integer whose value is less than 0 (zero) if wcstring1 is less
than wcstring2.
No return value is reserved to indicate an error condition for any of these functions.
RELATED INFORMATION
Functions: strncat(3), wcscat(3), wcschr(3), wcscoll(3), wcslen(3), wcsspn(3)
Standards: standards(5) delim off
wcsncat(3)