casa::DirectoryIterator Class Reference [OS_module]

Traverse the contents of a directory. More...

#include <DirectoryIterator.h>

List of all members.

Public Member Functions
	DirectoryIterator ()
	Construct the iterator for the working directory.
	DirectoryIterator (const Directory &dir)
	Construct the iterator for the given directory.
	DirectoryIterator (const Directory &dir, const Regex &regExpression)
	Construct the iterator for the given directory.
	DirectoryIterator (const DirectoryIterator &that)
	Copy constructor (copy semantics).
DirectoryIterator &	operator= (const DirectoryIterator &that)
	Assignment (copy semantics).
	~DirectoryIterator ()
void	operator++ ()
	Position on the next matching entry in the directory.
void	operator++ (int)
String	name () const
	Returns the file name at the current position.
File	file () const
	Returns a File object for the file at the current position.
void	reset ()
	Reposition the directory stream on the first entry.
Bool	pastEnd () const
	Checks if the iterator is past the end.
Private Member Functions
void	init ()
	Initialize the iterator.
Private Attributes
DIR *	itsDirectoryDescriptor
	This variable is used for seeking in the directory.
dirent *	itsDirectoryEntry
	This structure is used for information of the directory.
Bool	itsEnd
	Boolean to check if the directory stream has past the end.
Directory	itsDirectory
	class directory
Regex	itsExpression
	Regular expression if given, with this variable it is possible to compare files with regular expression.
dirent **	itsNameList
	Cray XT3 does not support readdir on compute nodes.
int	itsNrNames
int	itsNameInx

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Detailed Description

Traverse the contents of a directory.

Review Status

Reviewed By:

UNKNOWN

Date Reviewed:

before2004/08/25

Intended use:

Public interface

Prerequisite

• Basic knowledge of the UNIX file system
• Directory
• possibly Regex

Synopsis

DirectoryIterator allows to traverse a directory. In this way all file names in a directory can be gotten. Files . and .. will always be skipped.

By means of a regular expression it is possible to traverse the directory selectively. That is, only the file names matching the regular expression will be returned. Note that the regular expression is a true regular expression (as defined by class Regex and not a file expression as used in shells. Thus to get all .cc files, one has to specify ".*\.cc" and not "*.cc".

The File class can be used to determine if a file represents a symlink, directory or regular file.

Example

       Directory dir("testdir");
       // Get all .cc files.
       // Note that Regex is a true regular expression and not a
       // simplified file expression (like *.cc) as used in shells.
       DirectoryIterator dirIter(dir, ".*.\cc");
       while (!dirIter.pastEnd()){
          cout << dirIter.name() << endl;
          dirIter++;
       }

Motivation

With this class it is easy to iterate through a directory.

To Do

• Allow file expressions like *.cc. However, it's probably better to make that part of Regex.

Definition at line 91 of file DirectoryIterator.h.

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Constructor & Destructor Documentation

casa::DirectoryIterator::DirectoryIterator

(

)

Construct the iterator for the working directory.

All entries (except . and ..) will be traversed. It positions the iterator on the first entry.

casa::DirectoryIterator::DirectoryIterator

(

const Directory &

dir

)

Construct the iterator for the given directory.

All entries (except . and ..) will be traversed. It positions the iterator on the first entry.

casa::DirectoryIterator::DirectoryIterator	(	const Directory &	dir,
		const Regex &	regExpression
	)

Construct the iterator for the given directory.

All entries matching the regular expression will be traversed. It positions the iterator on the first entry.

casa::DirectoryIterator::DirectoryIterator

(

const DirectoryIterator &

that

)

Copy constructor (copy semantics).

The iterator will be positioned at the beginning.

casa::DirectoryIterator::~DirectoryIterator

(

)

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Member Function Documentation

File casa::DirectoryIterator::file

(

)

const

Returns a File object for the file at the current position.

Note that this adds the path of the directory to get the correct path for the file.
An exception is thrown if the iterator is already past the end.

void casa::DirectoryIterator::init

(

)

[private]

Initialize the iterator.

String casa::DirectoryIterator::name

(

)

const

Returns the file name at the current position.

An exception is thrown if the iterator is already past the end.

void casa::DirectoryIterator::operator++

(

)

Position on the next matching entry in the directory.

An exception is thrown if the iterator is already past the end.

void casa::DirectoryIterator::operator++

(

int

)

DirectoryIterator& casa::DirectoryIterator::operator=

(

const DirectoryIterator &

that

)

Assignment (copy semantics).

The iterator will be positioned at the beginning.

Bool casa::DirectoryIterator::pastEnd

(

)

const

Checks if the iterator is past the end.

void casa::DirectoryIterator::reset

(

)

Reposition the directory stream on the first entry.

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Member Data Documentation

Directory casa::DirectoryIterator::itsDirectory [private]

class directory

Definition at line 102 of file DirectoryIterator.h.

DIR* casa::DirectoryIterator::itsDirectoryDescriptor [private]

This variable is used for seeking in the directory.

The directory is opened and closed once during the lifetime of the class.

Definition at line 93 of file DirectoryIterator.h.

dirent* casa::DirectoryIterator::itsDirectoryEntry [private]

This structure is used for information of the directory.

Definition at line 96 of file DirectoryIterator.h.

Bool casa::DirectoryIterator::itsEnd [private]

Boolean to check if the directory stream has past the end.

Definition at line 99 of file DirectoryIterator.h.

Regex casa::DirectoryIterator::itsExpression [private]

Regular expression if given, with this variable it is possible to compare files with regular expression.

Definition at line 106 of file DirectoryIterator.h.

int casa::DirectoryIterator::itsNameInx [private]

Definition at line 112 of file DirectoryIterator.h.

dirent** casa::DirectoryIterator::itsNameList [private]

Cray XT3 does not support readdir on compute nodes.

Use scandir instead.

Definition at line 110 of file DirectoryIterator.h.

int casa::DirectoryIterator::itsNrNames [private]

Definition at line 111 of file DirectoryIterator.h.

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

• casa/OS/DirectoryIterator.h