twisted.application.runner._pidfile.NonePIDFile(object) class documentationtwisted.application.runner._pidfile
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Known subclasses: twisted.application.runner.test.test_runner.DummyPIDFile
Implements interfaces: twisted.application.runner._pidfile.IPIDFile
PID file implementation that does nothing.
This is meant to be used as a "active None" object in place of a PID file when no PID file is desired.
| Method | __init__ | Undocumented | 
| Method | read | Read the process ID stored in this PID file. | 
| Method | writeRunningPID | Store the PID of the current process in this PID file. | 
| Method | remove | Remove this PID file. | 
| Method | isRunning | Determine whether there is a running process corresponding to the PID in this PID file. | 
| Method | __enter__ | Enter a context using this PIDFile. | 
| Method | __exit__ | Exit a context using this PIDFile. | 
| Method | _write | Store a PID in this PID file. | 
Read the process ID stored in this PID file.
| Returns | The contained process ID. (type: int) | |
| Raises | NoPIDFound | If this PID file does not exist. | 
| EnvironmentError | If this PID file cannot be read. | |
| ValueError | If this PID file's content is invalid. | |
Store a PID in this PID file.
| Parameters | pid | A PID to store. (type: int) | 
| Raises | EnvironmentError | If this PID file cannot be written. | 
| Note | This implementation always raises an EnvironmentError. | |
Store the PID of the current process in this PID file.
| Raises | EnvironmentError | If this PID file cannot be written. | 
Determine whether there is a running process corresponding to the PID in this PID file.
| Returns | True if this PID file contains a PID and a process with that PID is 
currently running; false otherwise. (type: bool) | |
| Raises | EnvironmentError | If this PID file cannot be read. | 
| InvalidPIDFileError | If this PID file's content is invalid. | |
| StalePIDFileError | If this PID file's content refers to a PID for which there is no corresponding running process. | |
Enter a context using this PIDFile.
Writes the PID file with the PID of the running process.
| Raises | AlreadyRunningError | A process corresponding to the PID in this PID file is already running. | 
Exit a context using this PIDFile.
Removes the PID file.