ref: c537be1db2c051ae78bb53a71a1e83ed5efea1dd
dir: /sys/src/libc/port/strdup.c/
#include <u.h>
#include <libc.h>
char*
strdup(char *s)
{
char *ns;
ns = malloc(strlen(s) + 1);
if(ns == 0)
return 0;
setmalloctag(ns, getcallerpc(&s));
return strcpy(ns, s);
}