如果我按Ctrl C,这将抛出异常(总是在线程0？).如果你想要 – 或者更有可能运行一些清理,然后再推翻它,你可以抓住这个.但通常的结果是使程序以某种方式停止.
现在假设我使用了Unix kill命令.据了解,kill基本上会向指定的进程发送一个(可配置的)Unix信号.
Haskell RTS如何回应？是否记录在某个地方？我会想象发送SIGTERM将具有与Ctrl C相同的效果,但我不知道一个事实…
(当然,你可以使用kill来发送与杀戮毫无关系的信号,同样,我想象RTS会忽略SIGHUP或SIGPWR,但我不知道.)
在
ghc source code的github上搜索“signal”显示了
installDefaultSignals的功能：
void
initDefaultHandlers(void)
{
struct sigaction action,oact;
// install the SIGINT handler
action.sa_handler = shutdown_handler;
sigemptyset(&action.sa_mask);
action.sa_flags = 0;
if (sigaction(SIGINT,&action,&oact) != 0) {
sysErrorBelch("warning: Failed to install SIGINT handler");
}
#if defined(HAVE_SIGINTERRUPT)
siginterrupt(SIGINT,1); // isn't this the default? --SDM
#endif
// install the SIGFPE handler
// In addition to handling SIGINT,also handle SIGFPE by ignoring it.
// Apparently IEEE requires floating-point exceptions to be ignored by
// default,but alpha-dec-osf3 doesn't seem to do so.
// Commented out by SDM 2/7/2002: this causes an infinite loop on
// some architectures when an integer division by zero occurs: we
// don't recover from the floating point exception,and the
// program just generates another one immediately.
#if 0
action.sa_handler = SIG_IGN;
sigemptyset(&action.sa_mask);
action.sa_flags = 0;
if (sigaction(SIGFPE,&oact) != 0) {
sysErrorBelch("warning: Failed to install SIGFPE handler");
}
#endif
#ifdef alpha_HOST_ARCH
ieee_set_fp_control(0);
#endif
// ignore SIGPIPE; see #1619
// actually,we use an empty signal handler rather than SIG_IGN,// so that SIGPIPE gets reset to its default behavIoUr on exec.
action.sa_handler = empty_handler;
sigemptyset(&action.sa_mask);
action.sa_flags = 0;
if (sigaction(SIGPIPE,&oact) != 0) {
sysErrorBelch("warning: Failed to install SIGPIPE handler");
}
set_sigtstp_action(rtsTrue);
}
从那里可以看出,GHC至少安装了SIGINT和SIGPIPE处理程序.我不知道是否有其他的信号处理程序隐藏在源代码中.
