Now, the application has been tweaked so different modes of echoing are available
1) sequential - the file is read line-by-line. Line is output before next is read.
2) parallel - when a line is read a function is spawned to output it => process spawned per line.
3) pooled - file is read line-by-line. Line is output via the pool of workers.

pooled does not show its usefulness yet. For a single file, the performance is the same as the sequential mode.