pw_dup
if ((old_pwd = pw_dup(pwd)) == NULL)
*pw_dup(const struct passwd *_pw);
ret = pw_dup(&pw);
if ((pw = pw_dup(pw)) == NULL ||
(old_pw = pw_dup(pw)) == NULL)
if ((pw = pw_dup(pw)) == NULL)
return (pw_dup(pw));
pw = pw_dup(pwd);
nispwd = pw_dup(pwd);
pw = pw_dup(pwd);