An operating-system-independent modular programming method is disclosed, which includes providing one or more tasks, one or more task queues, and zero or more condition queues. Each task is a program that is run in sequence. Each task queue includes a task queue program and a queue containing zero or more tasks. Each condition queue includes a condition queue program and a queue containing zero or more tasks and associated conditions. Each task includes task ending code that refers to zero, one, or more than one successor task, and the task queue program or the condition queue program handles each such successor task by either running it or placing it in a task queue or a condition queue. The programming method further includes providing a fan and an end fan construct to enable a parent task to generate a plurality of child sequences. These program constructs may be used to form pseudothreads, each pseudothread being a single sequence of control, with interruptions allowed but no concurrency of execution, implemented in an operating system independent way. Also disclosed is an application of this programming method to accomplish robust just-in-time response to multiple asynchronous data streams in a RAID control program. The RAID control program includes a plurality of requesters, a resource allocator, and a plurality of stripe parity and IO masters, and an optional chainer, each being implemented as a pseudothread.