The QtConcurrent namespace provides high-level APIs that make it possible to write multi-threaded programs without using low-level threading primitives for Linux.

使用QtConcurrent提供的Map-Reduce并行执行API来计算较大文件的Checksum值。 QtConcurrent会根据CPU的Core Processer个数来自动分配线程数。(A file checksum computation program of Qt.)