Documentation
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Index ¶
Constants ¶
const ( MarkName = "_GO_DAEMON" MarkValue = "1" )
Mark of daemon process - system environment variable _GO_DAEMON=1
const FilePerm = os.FileMode(0640)
FilePerm set default file permissions for log and pid files.
Variables ¶
var ErrStop = errors.New("stop serve signals")
ErrStop should be returned signal handler function for termination of handling signals.
var ( // ErrWouldBlock indicates on locking pid-file by another process. ErrWouldBlock = syscall.EWOULDBLOCK )
Functions ¶
func ReadPidFile ¶
ReadPidFile reads process id from file with give name and returns pid. If unable read from a file, returns error.
func SetSigHandler ¶
func SetSigHandler(handler SignalHandlerFunc, signals ...os.Signal)
SetSigHandler sets handler for the given signals. SIGTERM has the default handler, he returns ErrStop.
Types ¶
type Context ¶
type Context struct {
// If PidFileName is non-empty, parent process will try to create and lock
// pid file with given name. Child process writes process id to file.
PidFileName string
// Permissions for new pid file.
PidFilePerm os.FileMode
// If LogFileName is non-empty, parent process will create file with given name
// and will link to fd 2 (stderr) for child process.
LogFileName string
// Permissions for new log file.
LogFilePerm os.FileMode
// If WorkDir is non-empty, the child changes into the directory before
// creating the process.
WorkDir string
// If Chroot is non-empty, the child changes root directory
Chroot string
// If Env is non-nil, it gives the environment variables for the
// daemon-process in the form returned by os.Environ.
// If it is nil, the result of os.Environ will be used.
Env []string
// If Args is non-nil, it gives the command-line args for the
// daemon-process. If it is nil, the result of os.Args will be used
// (without program name).
Args []string
// Credential holds user and group identities to be assumed by a daemon-process.
Credential *syscall.Credential
// If Umask is non-zero, the daemon-process call Umask() func with given value.
Umask int
// contains filtered or unexported fields
}
A Context describes daemon context.
func (*Context) Reborn ¶
Reborn runs second copy of current process in the given context. function executes separate parts of code in child process and parent process and provides demonization of child process. It look similar as the fork-daemonization, but goroutine-safe. In success returns *os.Process in parent process and nil in child process. Otherwise returns error.
type LockFile ¶
LockFile wraps *os.File and provide functions for locking of files.
func CreatePidFile ¶
CreatePidFile opens the named file, applies exclusive lock and writes current process id to file.
func NewLockFile ¶
NewLockFile returns a new LockFile with the given File.
func OpenLockFile ¶
OpenLockFile opens the named file with flags os.O_RDWR|os.O_CREATE and specified perm. If successful, function returns LockFile for opened file.
func (*LockFile) Lock ¶
Lock apply exclusive lock on an open file. If file already locked, returns error.
func (*LockFile) ReadPid ¶
ReadPid reads process id from file and returns pid. If unable read from a file, returns error.
type SignalHandlerFunc ¶
SignalHandlerFunc is the interface for signal handler functions.
Source Files