Function kern_getenv

freebsd/kern/kern_environment.c:480–502

* Look up an environment variable by name. * Return a pointer to the string if found. * The pointer has to be freed with freeenv() * after use. */

 * after use.
 */
char *
kern_getenv(const char *name)
{
	char *cp, *ret;
	int len;

	if (dynamic_kenv) {
		len = KENV_MNAMELEN + 1 + kenv_mvallen + 1;
		ret = uma_zalloc(kenv_zone, M_WAITOK | M_ZERO);
		mtx_lock(&kenv_lock);
		cp = _getenv_dynamic(name, NULL);
		if (cp != NULL)
			strlcpy(ret, cp, len);
		mtx_unlock(&kenv_lock);
		if (cp == NULL) {
			uma_zfree(kenv_zone, ret);
			ret = NULL;
		}
	} else
		ret = _getenv_static(name);

	return (ret);
}

/*
 * Test if an environment variable is defined.