Re: dd hangs with SIGINT

[Bruno Haible]

Jim Meyering wrote:
> Thanks for the patch, but that `cure' seems worse than the disease.

I agree. The real good way to make this work on POSIX systems (without
assuming multithreading) is to use fork().

  - Let the parent process fork a child process, block the signals SIGHUP,
    SIGQUIT, SIGPIPE in the parent, and watch the child's exit status.
    If the exit status of the child is 128 + SIGHUP/SIGQUIT/SIGPIPE,
    print the statistics.
  - Let the child process to the real I/O work.

With this approach, you don't install any signal handlers, therefore you
don't even need to think about which functions are async-signal safe. You
can use full malloc(), quote(), ngettext(), fprintf() etc. at will.

Bruno