ref: f0f2d452c873255dec4b3359b3f93e349be0f2c5
dir: /sys/src/ape/lib/ap/gen/memchr.c/
#include <string.h>
void*
memchr(const void *ap, int c, size_t n)
{
unsigned char *sp;
sp = (unsigned char*)ap;
c &= 0xFF;
while(n > 0) {
if(*sp++ == c)
return sp-1;
n--;
}
return 0;
}