Originální popis anglicky: 
wmemchr - find a wide character in memory
Návod, kniha: POSIX Programmer's Manual
#include <wchar.h>
 
 
wchar_t *wmemchr(const wchar_t * 
ws, wchar_t
  wc, size_t n);
 
The 
wmemchr() function shall locate the first occurrence of 
wc in
  the initial 
n wide characters of the object pointed to by 
ws.
  This function shall not be affected by locale and all 
wchar_t values
  shall be treated identically. The null wide character and 
wchar_t
  values not corresponding to valid characters shall not be treated specially.
If 
n is zero, the application shall ensure that 
ws is a valid
  pointer and the function behaves as if no valid occurrence of 
wc is
  found.
The 
wmemchr() function shall return a pointer to the located wide
  character, or a null pointer if the wide character does not occur in the
  object.
No errors are defined.
The following sections are informative.
None.
None.
None.
None.
wmemcmp() , 
wmemcpy() , 
wmemmove() , 
wmemset() , the
  Base Definitions volume of IEEE Std 1003.1-2001,
  
<wchar.h>
Portions of this text are reprinted and reproduced in electronic form from IEEE
  Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable
  Operating System Interface (POSIX), The Open Group Base Specifications Issue
  6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics
  Engineers, Inc and The Open Group. In the event of any discrepancy between
  this version and the original IEEE and The Open Group Standard, the original
  IEEE and The Open Group Standard is the referee document. The original
  Standard can be obtained online at http://www.opengroup.org/unix/online.html
  .