A ROOT file.

A ROOT file is an object store: it can serialize any object for which ROOT I/O is available (generally: an object which has a dictionary), and it stores the object's data under a key name.

Definition at line 45 of file TFile.hxx.

Classes
struct	Options_t
	Options for TFile construction. More...

Public Member Functions
	~TFile ()
	Must not call Write() of all attached objects: some might not be needed to be written or writing might be aborted due to an exception; require explicit Write(). More...

void	Close ()
	Flush() and make the file non-writable: close it. More...

void	Flush ()
	Save all objects associated with this directory (including file header) to the storage medium. More...

template<class T >
std::unique_ptr< T >	Read (std::string_view name)
	Read the object for a key. More...

template<class T >
void	Write (std::string_view name, const T &obj)
	Write an object that is not lifetime managed by this TFileImplBase. More...

template<class T >
void	Write (std::string_view name, const T *obj)
	Write an object that is not lifetime managed by this TFileImplBase. More...

void	Write (std::string_view name)
	Write an object that is already lifetime managed by this TFileImplBase. More...

template<class T >
void	Write (std::string_view name, std::shared_ptr< T > &&obj)
	Hand over lifetime management of an object to this TFileImplBase, and write it. More...

Public Member Functions inherited from ROOT::Experimental::TDirectory
template<class T >
void	Add (std::string_view name, const std::shared_ptr< T > &ptr)
	Add an existing object (rather a `shared_ptr` to it) to the TDirectory. More...

template<class T , class... ARGS>
std::shared_ptr< ToContentType_t< T > >	Create (std::string_view name, ARGS &&... args)
	Create an object of type `T` (passing some arguments to its constructor). More...

Internal::TDirectoryEntry	Find (std::string_view name) const
	Find the TDirectoryEntry associated to the name. More...

template<class T >
std::pair< Internal::TDirectoryEntry, EFindStatus >	Find (std::string_view name) const
	Find the TDirectoryEntry associated with the name. More...

template<class T >
std::shared_ptr< ToContentType_t< T > >	Get (std::string_view name)
	Get the object for a key. More...

Static Public Member Functions
static std::string	GetCacheDir ()
	Get the directory used for cached reads. More...

static std::string	SetCacheDir (std::string_view path)
	Set the new directory used for cached reads, returns the old directory. More...

Generator functions
static TFilePtr	Open (std::string_view name, const Options_t &opts=Options_t())
	Open a file with `name` for reading. More...

static TFilePtr	OpenForUpdate (std::string_view name, const Options_t &opts=Options_t())
	Open an existing file with `name` for reading and writing. More...

static TFilePtr	Create (std::string_view name, const Options_t &opts=Options_t())
	Open a file with `name` for reading and writing. More...

static TFilePtr	Recreate (std::string_view name, const Options_t &opts=Options_t())
	Open a file with `name` for reading and writing. More...

Static Public Member Functions inherited from ROOT::Experimental::TDirectory
static TDirectory &	Heap ()
	Dedicated, process-wide TDirectory. More...

Private Member Functions
	TFile (std::unique_ptr< Internal::TFileStorageInterface > &&storage)

void	WriteMemoryWithType (std::string_view name, const void address, TClass cl)
	Serialize the object at address, using the object's TClass. More...

Private Attributes
std::unique_ptr< Internal::TFileStorageInterface >	fStorage
	Storage backend. More...

Additional Inherited Members
Public Types inherited from ROOT::Experimental::TDirectory
enum	EFindStatus { EFindStatus::kValidValue, EFindStatus::kValidValueBase, EFindStatus::kKeyNameNotFound, EFindStatus::kTypeMismatch }
	Status of the call to Find<T>(name). More...

#include <ROOT/TFile.hxx>

Inheritance diagram for ROOT::Experimental::TFile:

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Constructor & Destructor Documentation

◆ TFile()

TFile::TFile ( std::unique_ptr< Internal::TFileStorageInterface > && storage )

private

Definition at line 206 of file TFile.cxx.

◆ ~TFile()

TFile::~TFile ( )

default

Must not call Write() of all attached objects: some might not be needed to be written or writing might be aborted due to an exception; require explicit Write().

Member Function Documentation

◆ Close()

void TFile::Close ( )

Flush() and make the file non-writable: close it.

Definition at line 218 of file TFile.cxx.

◆ Create()

ROOT::Experimental::TFilePtr TFile::Create	(	std::string_view	name,
		const Options_t &	opts = `Options_t()`
	)

static

Open a file with name for reading and writing.

Fail (return an invalid TFilePtr) if a file with this name already exists.

Note: : Synchronizes multi-threaded accesses through locks.

Definition at line 162 of file TFile.cxx.

◆ Flush()

void TFile::Flush ( )

Save all objects associated with this directory (including file header) to the storage medium.

Definition at line 214 of file TFile.cxx.

◆ GetCacheDir()

std::string TFile::GetCacheDir ( )

static

Get the directory used for cached reads.

Definition at line 198 of file TFile.cxx.

◆ Open()

ROOT::Experimental::TFilePtr TFile::Open	(	std::string_view	name,
		const Options_t &	opts = `Options_t()`
	)

static

Open a file with name for reading.

Note: : Synchronizes multi-threaded accesses through locks.

Definition at line 153 of file TFile.cxx.

◆ OpenForUpdate()

ROOT::Experimental::TFilePtr TFile::OpenForUpdate	(	std::string_view	name,
		const Options_t &	opts = `Options_t()`
	)

static

Open an existing file with name for reading and writing.

If a file with that name does not exist, an invalid TFilePtr will be returned.

Note: : Synchronizes multi-threaded accesses through locks.

Definition at line 180 of file TFile.cxx.

◆ Read()

template<class T >

std::unique_ptr<T> ROOT::Experimental::TFile::Read ( std::string_view name )

inline

Read the object for a key.

T must be the object's type. This will re-read the object for each call, returning a new copy; whether the TDirectory is managing an object attached to this key or not.

Returns: a unique_ptr to the object.

Exceptions

TDirectoryUnknownKey	if no object is stored under this name.
TDirectoryTypeMismatch	if the object stored under this name is of a type different from `T`.

Definition at line 134 of file TFile.hxx.

◆ Recreate()

ROOT::Experimental::TFilePtr TFile::Recreate	(	std::string_view	name,
		const Options_t &	opts = `Options_t()`
	)

static

Open a file with name for reading and writing.

If a file with this name already exists, delete it and create a new one. Else simply create a new file.

Note: : Synchronizes multi-threaded accesses through locks.

Definition at line 171 of file TFile.cxx.

◆ SetCacheDir()

std::string TFile::SetCacheDir ( std::string_view path )

static

Set the new directory used for cached reads, returns the old directory.

Note: : Synchronizes multi-threaded accesses through locks.

Definition at line 189 of file TFile.cxx.

◆ Write() [1/4]

template<class T >

void ROOT::Experimental::TFile::Write	(	std::string_view	name,
		const T &	obj
	)

inline

Write an object that is not lifetime managed by this TFileImplBase.

Definition at line 146 of file TFile.hxx.

◆ Write() [2/4]

template<class T >

void ROOT::Experimental::TFile::Write	(	std::string_view	name,
		const T *	obj
	)

inline

Write an object that is not lifetime managed by this TFileImplBase.

Definition at line 153 of file TFile.hxx.

◆ Write() [3/4]

void ROOT::Experimental::TFile::Write ( std::string_view name )

inline

Write an object that is already lifetime managed by this TFileImplBase.

Definition at line 159 of file TFile.hxx.

◆ Write() [4/4]

template<class T >

void ROOT::Experimental::TFile::Write	(	std::string_view	name,
		std::shared_ptr< T > &&	obj
	)

inline

Hand over lifetime management of an object to this TFileImplBase, and write it.

Definition at line 168 of file TFile.hxx.

◆ WriteMemoryWithType()

void TFile::WriteMemoryWithType	(	std::string_view	name,
		const void *	address,
		TClass *	cl
	)

private

Serialize the object at address, using the object's TClass.

Definition at line 222 of file TFile.cxx.

Member Data Documentation

◆ fStorage

std::unique_ptr<Internal::TFileStorageInterface> ROOT::Experimental::TFile::fStorage

private

Storage backend.

Definition at line 47 of file TFile.hxx.

Libraries for ROOT::Experimental::TFile:

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Classes

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Constructor & Destructor Documentation

◆ TFile()

◆ ~TFile()

Member Function Documentation

◆ Close()

◆ Create()

◆ Flush()

◆ GetCacheDir()

◆ Open()

◆ OpenForUpdate()

◆ Read()

◆ Recreate()

◆ SetCacheDir()

◆ Write() [1/4]

◆ Write() [2/4]

◆ Write() [3/4]

◆ Write() [4/4]

◆ WriteMemoryWithType()

Member Data Documentation

◆ fStorage