Can't cancel download with `ctrl-c`

[molomby]

When a download is active (eg. after running b2 download-file-by-id) it cannot be interrupted with a SIGINT (Ctrl+c) or EOF (Ctrl+c). Both cause the progress bar to be printed on a new line but have no other effect.

The SIGQUIT signal works (Ctrl+\) but, on MacOS at least, triggers an analytics collection dialogue:

[ppolewicz]

what happens if you click "show details"?

[mjurbanski-reef]

Please reopen if problem still occurs with current version.