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Re: [VANILLA-LIST:2237] xsg stuff
On Fri, 02 Apr 1999 you wrote:
>On Fri, Apr 02, 1999 at 12:13:36AM -0700, Jonathan Ellis wrote:
>>
>> out a frame. My question is this: IIANM, HANDLE_SIG and SIGNAL are both
>> #defined to the system call signal(). (Any reason why?)
>
>HANDLE_SIG and SIGNAL are redundant definitions.
Not really. There are three types of signals.
1) BSD signals. Once set they are active until you explicitly unset.
It defines
SIGNAL = signal
HANDLE_SIG =
2) POSIX signals. Automatically resets the signal handler after the signal
is caught and handled. It requires the signal to be set again in the handler.
It defines
SIGNAL = signal
HANDLE_SIG = signal
3) SYSV signals, behave like POSIX but you have an additional sigset
command which behaves like the BSD signal command.
It defines
SIGNAL = sigset
HANDLE_SIG =
>> Does the signal handler need to be re-specified after each interrupt,
>
>The handler needs to be reinstalled after the signal is caught and handled.
Only in case of pure POSIX signals. That's what the HANDLE_SIG
define is good for. Linux and Solaris have pure POSIX signals.
All three types are correctly autodetected.
Kurt (007)
--
Kurt Siegl / Franzberg 4, A-4483 Hargelsberg, Austria
Email: 007@netrek.org Tel (ISDN): *(7225)7017
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