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
memchr(src_void,c,length)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