+
+/**
+ * getenv_hex() - Return an environment variable as a hex value
+ *
+ * Decode an environment as a hex number (it may or may not have a 0x
+ * prefix). If the environment variable cannot be found, or does not start
+ * with hex digits, the default value is returned.
+ *
+ * @varname: Variable to decode
+ * @default_val: Value to return on error
+ */
+ulong getenv_hex(const char *varname, ulong default_val);
+
+/*
+ * Read an environment variable as a boolean
+ * Return -1 if variable does not exist (default to true)
+ */
+int getenv_yesno(const char *var);