multipart messages & delivery guarantees

Hi, Some events, such as execve or socket-related syscalls generate more than one message, which I'll separate as the "main" message, and then the 'sub' messages. Does the audit system guarantee in any way that user-mode will receive either no message, or all messages for a given event ? I'm curious to know if for example I could get an execve syscall message, but no cwd message, for example in case of low-memory condition. Thanks, Hassan