Function CWKeychainFindWiFiPassword 

pub unsafe extern "C-unwind" fn CWKeychainFindWiFiPassword(
    domain: CWKeychainDomain,
    ssid: &NSData,
    password: *mut *mut NSString,
) -> i32

Available on crate features CoreWLANTypes and CoreWLANUtil only.

Parameter domain: The keychain domain, which determines which keychain will be used.

Parameter ssid: The service set identifier (SSID) which is used to uniquely identify the keychain item.

Parameter password: An NSString passed by reference, which upon return will contain the Wi-Fi keychain password for the specified SSID. This parameter is optional.

Returns: An OSStatus error code indicating whether or not a failure occurred. errSecSuccess indicates no error occurred.

Finds and returns (by reference) the password for the specified SSID and keychain domain.

Safety

password must be a valid pointer or null.