# Functions
CreatePidFile opens the named file, applies exclusive lock and writes current process id to file.
GetFdName returns file name for given descriptor.
NewLockFile returns a new LockFile with the given File.
OpenLockFile opens the named file with flags os.O_RDWR|os.O_CREATE and specified perm.
ReadPidFile reads process id from file with give name and returns pid.
ServeSignals calls handlers for system signals.
SetSigHandler sets handler for the given signals.
WasReborn returns true in child process (daemon) and false in parent process.
# Variables
ErrStop should be returned signal handler function for termination of handling signals.
ErrWouldBlock indicates on locking pid-file by another process.
# Type aliases
SignalHandlerFunc is the interface for signal handler functions.