Index for Section 3

Alphabetical listing for W

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wmemcpy(3)
NAME
  wmemcpy, wmemchr, wmemcmp, wmemmove, wmemset - Perform memory operations on
  wide-character arrays

SYNOPSIS
  #include <wchar.h>

  wchar_t *wmemcpy(
	  wchar_t *wstr1,
	   const wchar_t *wstrs2,
	  size_t n );

  wchar_t *wmemchr(
	  const wchar_t *wstr,
	  wchar_t wc,
	  size_t n );

  int wmemcmp(
	  const wchar_t *wstr1,
	  const wchar_t *wstr2,
	  size_t n );

  wchar_t *wmemmove(
	  wchar_t *wstr1,
	  const wchar_t *wstr2,
	  size_t n );

  wchar_t *wmemset(
	  wchar_t *wstr,
	  wchar_t wc,
	  size_t n );

LIBRARY
  Standard C Library (libc)

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  wmemcpy(), wmemchr(), wmemcmp(), wmemmove(), wmemset(): XSH5.0

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

PARAMETERS
  *wstr
      Points to the location of a wide-character string.

  *wstr1
      Points to the location of a destination wide-character string.

  *wstr2
      Points to the location of a source wide-character string.

  wc  Specifies a wide character for which to search (except for the
      wmemset() case, in which wc is the target of the copy).

  n   Specifies the number of wide characters to search.

DESCRIPTION
  The wmemcpy(), wmemchr(), wmemcmp(), wmemset(), and wmemmove() functions
  operate on wide-character strings in memory areas. A memory area is a group
  of contiguous wide characters bound by a count and not terminated by a null
  wide character.  These memory functions do not check for overflow of the
  receiving memory area.  They are also not affected by locale; therefore,
  they do not give special treatment to a null wide character or wide-
  character values that do not correspond to valid multibyte characters.
  Unless stated otherwise, these functions order two wide characters the same
  way as two integers of the integral type wchar_t. All of these memory
  functions are declared in the wchar.h header file.

  The wmemcpy() function copies n wide characters from the string pointed to
  by the wstr2 parameter into the location pointed to by the wstr1 parameter.
  When copying overlapping strings, the behavior of this function is
  unreliable.

  The wmemchr() function sequentially searches the wide-character string at
  the location pointed to by the wstr parameter until one of the following
  occurs:

    ·  The wide character specified by the wc parameter has been found.

    ·  The number of wide characters specified by the n parameter have been
       searched at location wstr.

  If wc is found, the wmemchr() function returns a pointer to that wide
  character in the string pointed to by wstr. If wc is not found after
  searching n wide characters, the function returns a null pointer.

  The wmemcmp() function compares the first n wide characters of the string
  pointed to by the wstr1 parameter with the first n wide characters of the
  string pointed to by the wstr2 parameter.

  This function returns one of the following values:

    ·  Less than zero if the value of the object in wstr1 is less than the
       value of the object in wstr2

    ·  Zero if the value of object in wstr1 is equal to the value of the
       object in wstr2

    ·  Greater than zero if the value of the object in wstr1 is greater than
       the value of the object in wstr2

  The wmemset() function first copies the value of the wide character
  specified by the wc parameter into each of the first n locations of the
  string pointed to by the wstr parameter and then returns the value of wstr.

  The wmemmove() function copies n wide characters from the string at the
  location pointed to by the wstr2 parameter to the string at the location
  pointed to by the wstr1 parameter. Copying takes place as though the n wide
  characters from string wstr2 are first copied into a temporary array having
  n wide characters that does not overlap either of the strings pointed to by
  wstr1 or wstr2. Then, n number of wide characters from the temporary array
  are copied to the string pointed to by wstr1. Consequently, this operation
  is nondestructive and proceeds from left to right. The wmemmove() function
  returns the value of wstr1.

  When the value of n is zero, all these functions either return zero or copy
  zero wide characters, depending on whether the purpose of the function is
  to compare or copy wide characters.

RETURN VALUES
  The wmemchr() function returns a pointer to the location of wc in wstr or a
  null pointer if wc is not found in the first n wide characters of wstr.

  The wmemcmp() function returns a value greater than, equal to, or less than
  0 (zero), according to whether the first n wide characters of the string
  pointed to by the wstr1 parameter have a value greater than, equal to, or
  less than the first n wide characters in the string pointed to by the wstr2
  parameter.

  The wmemcpy() and wmemmove() functions return the wide-character string
  pointed to by the wstr1 parameter.

  The wmemset() function returns the wide-character string pointed to by the
  wstr parameter.

SEE ALSO
  Functions: bcopy(3), memccpy(3), string(3), swab(3), wcscat(3), wcsspn(3),
  wcsstr(3), wcswcs(3)

Index for Section 3

Alphabetical listing for W

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