isc::util::PIDFile Class Reference

Class to help with processing PID files. More...

#include <pid_file.h>

Public Member Functions
	PIDFile (const std::string &filename)
	Constructor.
virtual	~PIDFile ()=default
	Destructor.
int	check () const
	Read the PID in from the file and check it.
void	deleteFile () const
	Delete the PID file.
std::string	getFilename () const
	Returns the path to the PID file.
std::string	getLockname () const
	Returns the path to the lock file.
void	write () const
	Get PID of the current process and write it to the file.
void	write (int) const
	Write the PID to the file.

Detailed Description

Class to help with processing PID files.

This is a utility class to manipulate PID file. It provides functions for writing and deleting a file containing a PID as well as for extracting a PID from a file and checking if the process is still running.

Definition at line 40 of file pid_file.h.

Constructor & Destructor Documentation

PIDFile()

isc::util::PIDFile::PIDFile ( const std::string & filename )

inline

Constructor.

Parameters

filename

PID filename.

Definition at line 45 of file pid_file.h.

~PIDFile()

virtual isc::util::PIDFile::~PIDFile ( )

virtualdefault

Destructor.

Member Function Documentation

check()

int isc::util::PIDFile::check

(

)

const

Read the PID in from the file and check it.

Read the PID in from the file then use it to see if a process with that PID exists. If the file doesn't exist treat it as the process not being there. If the file exists but can't be read or it doesn't have the proper format treat it as the process existing.

The PID file should be locked to avoid a race condition.

Returns

returns the PID if it is in, 0 otherwise.

Exceptions

throws

PIDCantReadPID if it was able to open the file but was unable to read the PID from it.

Definition at line 23 of file pid_file.cc.

References isc_throw.

Referenced by isc::dhcp::LFCSetup::execute(), isc::dhcp::Memfile_LeaseMgr::isLFCProcessRunning(), and isc::lfc::LFCController::launch().

deleteFile()

void isc::util::PIDFile::deleteFile

(

)

const

Delete the PID file.

This is an atomic operation not subject to a race condition.

Exceptions

throws

PIDFileError if it can't delete the PID file

Definition at line 81 of file pid_file.cc.

References isc_throw.

Referenced by isc::dhcp::LFCSetup::execute(), and isc::lfc::LFCController::launch().

getFilename()

std::string isc::util::PIDFile::getFilename ( ) const

inline

Returns the path to the PID file.

Definition at line 92 of file pid_file.h.

getLockname()

std::string isc::util::PIDFile::getLockname ( ) const

inline

Returns the path to the lock file.

Definition at line 97 of file pid_file.h.

Referenced by isc::dhcp::LFCSetup::execute(), isc::dhcp::Memfile_LeaseMgr::isLFCProcessRunning(), and isc::lfc::LFCController::launch().

write() [1/2]

void isc::util::PIDFile::write

(

)

const

Get PID of the current process and write it to the file.

The PID file must be locked to avoid a race condition.

Exceptions

throws

PIDFileError if it can't open or write to the PID file.

Definition at line 55 of file pid_file.cc.

References write().

Referenced by write().

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write() [2/2]

void isc::util::PIDFile::write

(

int

pid

)

const

Write the PID to the file.

The PID file must be locked to avoid a race condition.

Parameters

pid	the pid to write to the file.

Exceptions

throws

PIDFileError if it can't open or write to the PID file.

Definition at line 60 of file pid_file.cc.

References isc_throw.

Referenced by isc::dhcp::LFCSetup::execute(), and isc::lfc::LFCController::launch().

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

• pid_file.h
• pid_file.cc