Re: Signal handling

[Ben Pfaff]

John Darrington <address@hidden> writes:

> In March last, you made this change to main.c shortly after I had
> added the bug_handler function:  

Changelog says this:

        Wed Mar  3 09:30:09 2004  Ben Pfaff  <address@hidden>

        * main.c: (main) sigaction()'s sa_flags member was uninitialized.
        Just use signal() instead.

If you use sigaction, initialize all the members.  It has three,
see the GNU libc manual:

 - Data Type: struct sigaction
     Structures of type `struct sigaction' are used in the `sigaction'
     function to specify all the information about how to handle a
     particular signal.  This structure contains at least the following
     members:

    `sighandler_t sa_handler'
          This is used in the same way as the ACTION argument to the
          `signal' function.  The value can be `SIG_DFL', `SIG_IGN', or
          a function pointer.  *Note Basic Signal Handling::.

    `sigset_t sa_mask'
          This specifies a set of signals to be blocked while the
          handler runs.  Blocking is explained in *Note Blocking for
          Handler::.  Note that the signal that was delivered is
          automatically blocked by default before its handler is
          started; this is true regardless of the value in `sa_mask'.
          If you want that signal not to be blocked within its handler,
          you must write code in the handler to unblock it.

    `int sa_flags'
          This specifies various flags which can affect the behavior of
          the signal.  These are described in more detail in *Note
          Flags for Sigaction::.

I don't think I had any other objection.
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