Name

SPVM::Sys::Signal - Signal System Call

Usage

use Sys::Signal;
use Sys::Signal::Constant as SIGNAL;

Sys::Signal->raise(SIGNAL->SIGTERM);

Sys::Signal->kill($process_id, SIGNAL->SIGINT);

Sys::Signal->signal(SIGNAL->SIGTERM, Sys::Signal->SIG_IGN);

Description

Sys::Signal provides the methods to call the system call for the signal.

Class Variables

$SIG_DFL

our $SIG_DFL : ro Sys::Signal::Handler::Default;

Gets a singlton Sys::Signal::Handler::Default object that represents SIG_DFL in C Language.

$SIG_IGN

our $SIG_IGN : ro Sys::Signal::Handler::Ignore;

Gets a singlton Sys::Signal::Handler::Ignore object that represents SIG_IGN in C Language.

$SIG_MONITOR

our $SIG_MONITOR : ro Sys::Signal::Handler::Monitor;

Gets a singlton Sys::Signal::Handler::Monitor object to monitor signals.

Class Methods

raise

static method raise : int ($sig : int)

The raise() function sends a signal to the calling process or thread.

See raise(3) - Linux man page in Linux.

Constant values specified in $sig is defined in Sys::Signal::Constant.

kill

static method kill : int ($pid : int, $sig : int)

The kill() system call can be used to send any signal to any process group or process.

See the kill(2) - Linux man page in Linux.

See Sys::Signal::Constant about the signal numbers specified by $sig

Constant values specified in $sig is defined in Sys::Signal::Constant.

alarm

static method alarm : int ($seconds : int)

alarm() arranges for a SIGALRM signal to be delivered to the calling process in seconds seconds.

See alarm(2) - Linux man page in Linux.

Examples:

Sys::Signal->reset_monitored_signal(SIGNAL->SIGALRM);

Sys::Signal->signal(SIGNAL->SIGALRM, Sys::Signal->SIG_MONITOR);

Sys::Signal->alarm(1);

while (1) {
  if (Sys::Signal->check_monitored_signal(SIGNAL->SIGALRM)) {
    # Do something
  }
}

ualarm

static method ualarm : int ($usecs : int, $interval : int)

The ualarm() function causes the signal SIGALRM to be sent to the invoking process after (not less than) usecs microseconds. The delay may be lengthened slightly by any system activity or by the time spent processing the call or by the granularity of system timers.

See ualarm(3) - Linux man page in Linux.

signal

static method signal : Sys::Signal::Handler ($signum : int, $handler : Sys::Signal::Handler);

signal() sets the disposition of the signal signum to handler.

See signal(2) - Linux man page in Linux.

Constant values specified in $signum is defined in Sys::Signal::Constant.

The $handler is a Sys::Signal::Handler object.

The well known Sys::Signal::Handler classes are Sys::Signal::Handler::Default, Sys::Signal::Handler::Ignore, Sys::Signal::Handler::Monitor, and Sys::Signal::Handler::Unknown.

Examples:

# SIG_DFL
Sys::Signal->signal(SIGNAL->SIGINT, Sys::Signal->SIG_DFL);

# SIG_IGN
Sys::Signal->signal(SIGNAL->SIGINT, Sys::Signal->SIG_IGN);

# Monitor signal
Sys::Signal->reset_monitored_signal(SIGNAL->SIGTERM);

my $old_handler = Sys::Signal->signal(SIGNAL->SIGTERM, Sys::Signal->SIG_MONITOR);

Sys::Signal->raise(SIGNAL->SIGTERM);

while (1) {
  if (Sys::Signal->check_monitored_signal(SIGNAL->SIGTERM)) {
    # Do something
  }
}

reset_monitored_signal

static method reset_monitored_signal : void ($signum : int);

Set a monitored signal by monitored Sys::Signal::Handler::Monitor to 0.

Constant values specified in $signum is defined in Sys::Signal::Constant.

check_monitored_signal

static method check_monitored_signal : int ($signum : int);

Gets a monitored signal by monitored Sys::Signal::Handler::Monitor.

If a signal is received, the monitored signal was set to 1 by the Sys::Signal::Handler::Monitor specified in the "signal" method.

Constant values specified in $signum is defined in Sys::Signal::Constant.

Copyright & License

Copyright (c) 2023 Yuki Kimoto

MIT License