1 /* 2 3 @deftypefn Supplemental void* memchr (const void *@var{s}, int @var{c}, size_t @var{n}) 4 5 This function searches memory starting at @code{*@var{s}} for the 6 character @var{c}. The search only ends with the first occurrence of 7 @var{c}, or after @var{length} characters; in particular, a null 8 character does not terminate the search. If the character @var{c} is 9 found within @var{length} characters of @code{*@var{s}}, a pointer 10 to the character is returned. If @var{c} is not found, then @code{NULL} is 11 returned. 12 13 @end deftypefn 14 15 */ 16 17 #include <ansidecl.h> 18 #ifdef ANSI_PROTOTYPES 19 #include <stddef.h> 20 #else 21 #define size_t unsigned long 22 #endif 23 24 PTR 25 memchr (src_void, c, length) 26 register const PTR src_void; 27 int c; 28 size_t length; 29 { 30 const unsigned char *src = (const unsigned char *)src_void; 31 32 while (length-- > 0) 33 { 34 if (*src == c) 35 return (PTR)src; 36 src++; 37 } 38 return NULL; 39 } 40