2 KiB
Construct Server
Construct is the executable running libircd. This application provides an
interface for the server administrator to start, stop, configure and locally
communicate with the daemon. It sets up an asio::io_service which is passed
to libircd, then it sets up signal handling, and then it runs the ios event
loop until commanded to exit.
This program executes in the foreground. It does not "daemonize" anymore with a
fork() etc. You are free to use your shell to execute or move the program
to the background, or simply use a tmux or screen. Construct will output
the libircd log to stdout and stderr by default.
Signals
Construct handles certain POSIX signals and their behavior is documented below. Prolonged ownership of any specific signal handler is not taken by libircd; only out here in the construct executable. libircd only makes cooperative use of signals: registering and deregistering any handlers stackfully in such a way that it is no concern to users of the library.
- Signal handling is accomplished through
boost::asio's mechanism which installs a handler to intercept the signal's delivery and posts it to the event loop for execution at the next event slice. This is how signal safety is achieved. Furthermore, according to boost docs, when signals are used this way they can be compatible with windows environments.
SIGQUIT
A ctrl-\ to Construct will cleanly shut down the server. It will not generate
a coredump.
SIGINT
A ctrl-c to Construct will bring up the command line console interface. It
will not halt the daemon. Log messages will be suppressed while the console
is waiting for input, but service is still continuing in the background.
SIGHUP
A "HangUP" to Construct is only relevant to the command line console, and
signals it to close like an EOF. The legacy functionality for reloading
server configuration et al is moved to SIGUSR1.
SIGUSR1
This signal commands the server to reload and refresh various aspects of its configuration and running state.