| Kea 3.0.2-git

isc::log::interprocess::InterprocessSyncFile Class Reference

File-based Interprocess Sync Class. More...

`#include <interprocess_sync_file.h>`

Inheritance diagram for isc::log::interprocess::InterprocessSyncFile:
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## Public Member Functions
| InterprocessSyncFile (const std::string &task_name)
| Constructor.
virtual | ~InterprocessSyncFile ()
| Destructor.
Public Member Functions inherited from isc::log::interprocess::InterprocessSync
| InterprocessSync (const std::string &task_name)
| Constructor.
virtual | ~InterprocessSync ()
| Destructor.

## Protected Member Functions
bool | lock ()
| Acquire the lock (blocks if something else has acquired a lock on the same task name).
bool | tryLock ()
| Try to acquire a lock (doesn't block).
bool | unlock ()
| Release the lock.

## Additional Inherited Members
Protected Attributes inherited from isc::log::interprocess::InterprocessSync
bool | is_locked_
| Is the lock taken?
const std::string | task_name_
| The task name.

## Detailed Description

File-based Interprocess Sync Class.

This class specifies a concrete implementation for a file-based interprocess synchronization mechanism. Please see the InterprocessSync class documentation for usage.

An InterprocessSyncFileError exception may be thrown if there is an issue opening the lock file.

Lock files are created typically in the local state directory (var). They are typically named like "<task_name>_lockfile". This implementation opens lock files lazily (only when necessary). It also leaves the lock files lying around as multiple processes may have locks on them.

Definition at line 42 of file interprocess_sync_file.h.

## Constructor & Destructor Documentation

## ◆ InterprocessSyncFile()

isc::log::interprocess::InterprocessSyncFile::InterprocessSyncFile | ( | const std::string & | task_name | ) |
| inline

Constructor.

Creates a file-based interprocess synchronization object

Parameters

  task_name | Name of the synchronization task. This has to be identical among the various processes that need to be synchronized for the same task.

Definition at line 51 of file interprocess_sync_file.h.

References isc::log::interprocess::InterprocessSync::InterprocessSync().

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## ◆ ~InterprocessSyncFile()

isc::log::interprocess::InterprocessSyncFile::~InterprocessSyncFile | ( |  | ) |
| virtual

Destructor.

Definition at line 31 of file interprocess_sync_file.cc.

## Member Function Documentation

## ◆ lock()

bool isc::log::interprocess::InterprocessSyncFile::lock | ( |  | ) |
| protected virtual

Acquire the lock (blocks if something else has acquired a lock on the same task name).

Returns
  Returns true if the lock was acquired, false otherwise.

Implements isc::log::interprocess::InterprocessSync.

Definition at line 89 of file interprocess_sync_file.cc.

References isc::log::interprocess::InterprocessSync::is_locked_.

## ◆ tryLock()

bool isc::log::interprocess::InterprocessSyncFile::tryLock | ( |  | ) |
| protected virtual

Try to acquire a lock (doesn't block).

Returns
  Returns true if the lock was acquired, false otherwise.

Implements isc::log::interprocess::InterprocessSync.

Definition at line 103 of file interprocess_sync_file.cc.

References isc::log::interprocess::InterprocessSync::is_locked_.

## ◆ unlock()

bool isc::log::interprocess::InterprocessSyncFile::unlock | ( |  | ) |
| protected virtual

Release the lock.

Returns
  Returns true if the lock was released, false otherwise.

Implements isc::log::interprocess::InterprocessSync.

Definition at line 117 of file interprocess_sync_file.cc.

References isc::log::interprocess::InterprocessSync::is_locked_.

The documentation for this class was generated from the following files:

- interprocess_sync_file.h
- interprocess_sync_file.cc