package singleinstance

import "git.sr.ht/~pingoo/stdx/singleinstance"

Package singleinstance provides a mechanism to ensure, that only one instance of a program is running

Index ¶

• Variables
• type Option
• func WithLockPath(lockpath string) Option
• type SingleInstance
• func New(name string, opts ...Option) *SingleInstance
• func (s *SingleInstance) Lock() error
• func (s *SingleInstance) Lockfile() string
• func (s *SingleInstance) Unlock() error

Examples ¶

• New

Variables ¶

var (
	// ErrAlreadyRunning another instance of is already running
	ErrAlreadyRunning = errors.New("another instance is already running")
)

Types ¶

type Option ¶

type Option func(*SingleInstance)

Option configures Single

func WithLockPath ¶

func WithLockPath(lockpath string) Option

WithLockPath configures the path for the lockfile

type SingleInstance ¶

type SingleInstance struct {
	// contains filtered or unexported fields
}

SingleInstance represents the name and the open file descriptor

func New ¶

func New(name string, opts ...Option) *SingleInstance

New creates a SingleInstance instance where name is the basename of the lock file (<name>.lock) if no path is given (WithLockPath option) the lock will be created in an operating specific path as <name>.lock panics if namr is empty

{
	// create a new lockfile in /var/lock/filename
	one := New("filename", WithLockPath("/tmp"))

	// lock and defer unlocking
	if err := one.Lock(); err != nil {
		log.Fatal(err)
	}

	// run

	if err := one.Unlock(); err != nil {
		log.Println(err)
	}
}

func (*SingleInstance) Lock ¶

func (s *SingleInstance) Lock() error

Lock tries to obtain an exclude lock on a lockfile and exits the program if an error occurs

func (*SingleInstance) Lockfile ¶

func (s *SingleInstance) Lockfile() string

Lockfile returns the full path of the lock file

func (*SingleInstance) Unlock ¶

func (s *SingleInstance) Unlock() error

Unlock releases the lock, closes and removes the lockfile

Source Files ¶

singleinstance.go singleinstance_unix.go