daemon

Documentation

Overview

Package daemon provides the entry point of the daemon sub-program and helpers to spawn a daemon process.

Index

• type Daemon
  • func (d *Daemon) Main(serve func(string, string)) error
  • func (d *Daemon) Spawn() error

Types

type Daemon

type Daemon struct {
	// BinPath is the path to the Elvish binary itself, used when forking. This
	// field is optional only when spawning the daemon.
	BinPath string
	// DbPath is the path to the database.
	DbPath string
	// SockPath is the path to the socket on which the daemon will serve
	// requests.
	SockPath string
	// LogPathPrefix is used to derive the name of the log file by adding the
	// pid.
	LogPathPrefix string
}

Daemon keeps configurations for the daemon sub-program. It can be used both from the main function for running the daemon and from another process (typically the first Elvish shell session) for spawning a daemon.

func (*Daemon) Main

func (d *Daemon) Main(serve func(string, string)) error

Main is the entry point of the daemon sub-program. It simply sets the umask (if relevant) and runs serve. It always return a nil error, since any errors encountered is logged in the serve function.

func (*Daemon) Spawn

func (d *Daemon) Spawn() error

Spawn spawns a daemon process in the background by invoking BinPath, passing DbPath, SockPath and LogPathPrefix as command-line arguments after resolving them to absolute paths. A suitable ProcAttr is chosen depending on the OS and makes sure that the daemon is detached from the current terminal (so that it is not affected by I/O or signals in the current terminal), and keeps running after the current process quits.