NSFileHandleMBS.fileHandleForReadingAtFile(path as folderitem) as NSFileHandleMBS

// file must exist for this sample:

dim f as FolderItem = SpecialFolder.Desktop.Child("test.txt")
dim n as NSFileHandleMBS = NSFileHandleMBS.fileHandleForReadingAtFile(f)

if n<>Nil then
  MsgBox n.readDataToEndOfFile
end if

path: The path to the file, device, or named socket to access.

Returns the initialized file handle, or nil if no file exists at path.

The file pointer is set to the beginning of the file. The returned object responds only to NSFileHandle read... messages.

Some examples using this method:

• /MacBase/NSFileHandle async reading

NSFileHandleMBS.fileHandleForReadingAtPath(path as string) as NSFileHandleMBS

path: The path to the file, device, or named socket to access.

Returns the initialized file handle, or nil if no file exists at path.

The file pointer is set to the beginning of the file. The returned object responds only to NSFileHandle read... messages.

NSFileHandleMBS.fileHandleForReadingFromFile(URL as folderitem, byref error as NSErrorMBS) as NSFileHandleMBS

// file must exist for this sample:

dim f as FolderItem = SpecialFolder.Desktop.Child("test.txt")
dim e as NSErrorMBS
dim n as NSFileHandleMBS = NSFileHandleMBS.fileHandleForReadingFromFile(f,e)

if e<>Nil then
  MsgBox e.localizedDescription
end if

if n<>Nil then
  MsgBox n.readDataOfLength(5)
  MsgBox str(n.offsetInFile) // shows 5
end if

url: The URL of the file, device, or named socket to access.
error: If an error occurs, upon return contains an NSError object that describes the problem.

Returns the initialized file handle, or nil if no file exists at url.

The file pointer is set to the beginning of the file. The returned object responds only to NSFileHandleread... messages.

NSFileHandleMBS.fileHandleForReadingFromURL(URL as string, byref error as NSErrorMBS) as NSFileHandleMBS

url: The URL of the file, device, or named socket to access.
error: If an error occurs, upon return contains an NSError object that describes the problem.

Returns the initialized file handle, or nil if no file exists at url.

The file pointer is set to the beginning of the file. The returned object responds only to NSFileHandleread... messages.

NSFileHandleMBS.fileHandleForUpdatingAtFile(path as folderitem) as NSFileHandleMBS

path: The path to the file, device, or named socket to access.

Returns the initialized file handle, or nil if no file exists at path.

The file pointer is set to the beginning of the file. The returned object responds to both NSFileHandle read... messages and writeData.

NSFileHandleMBS.fileHandleForUpdatingAtPath(path as string) as NSFileHandleMBS

path: The path to the file, device, or named socket to access.

Returns the initialized file handle, or nil if no file exists at path.

The file pointer is set to the beginning of the file. The returned object responds to both NSFileHandle read... messages and writeData.

NSFileHandleMBS.fileHandleForUpdatingFile(URL as folderitem, byref error as NSErrorMBS) as NSFileHandleMBS

url: The URL of the file, device, or named socket to access.
error: If an error occurs, upon return contains an NSError object that describes the problem.

The initialized file handle, or nil if no file exists at url.

The file pointer is set to the beginning of the file. The returned object responds to both NSFileHandleread... messages and writeData.

NSFileHandleMBS.fileHandleForUpdatingURL(URL as string, byref error as NSErrorMBS) as NSFileHandleMBS

url: The URL of the file, device, or named socket to access.
error: If an error occurs, upon return contains an NSError object that describes the problem.

The initialized file handle, or nil if no file exists at url.

The file pointer is set to the beginning of the file. The returned object responds to both NSFileHandleread... messages and writeData.

NSFileHandleMBS.fileHandleForWritingAtFile(path as folderitem) as NSFileHandleMBS

// file must exist for this sample:

dim f as FolderItem = SpecialFolder.Desktop.Child("test.txt")
dim n as NSFileHandleMBS = NSFileHandleMBS.fileHandleForWritingAtFile(f)

if n<>Nil then
  n.writeData "Hello World"
  n.closeFile
end if

path: The path to the file, device, or named socket to access.

Returns the initialized file handle, or nil if no file exists at path.

The file pointer is set to the beginning of the file. The returned object responds only to writeData.

NSFileHandleMBS.fileHandleForWritingAtPath(path as string) as NSFileHandleMBS

path: The path to the file, device, or named socket to access.

Returns the initialized file handle, or nil if no file exists at path.

The file pointer is set to the beginning of the file. The returned object responds only to writeData.

NSFileHandleMBS.fileHandleForWritingToFile(URL as folderitem, byref error as NSErrorMBS) as NSFileHandleMBS

// file must exist for this sample:

dim f as FolderItem = SpecialFolder.Desktop.Child("test.txt")
dim e as NSErrorMBS
dim n as NSFileHandleMBS = NSFileHandleMBS.fileHandleForWritingToFile(f, e)

if e<>Nil then
  MsgBox e.localizedDescription
else
  n.writeData "Hello World"
  n.closeFile
end if

url: The URL of the file, device, or named socket to access.
error: If an error occurs, upon return contains an NSError object that describes the problem.

Returns the initialized file handle, or nil if no file exists at url.

The file pointer is set to the beginning of the file. The returned object responds only to writeData.

NSFileHandleMBS.fileHandleForWritingToURL(URL as string, byref error as NSErrorMBS) as NSFileHandleMBS

url: The URL of the file, device, or named socket to access.
error: If an error occurs, upon return contains an NSError object that describes the problem.

Returns the initialized file handle, or nil if no file exists at url.

The file pointer is set to the beginning of the file. The returned object responds only to writeData.

NSFileHandleMBS.fileHandleWithFileDescriptor(fd as Integer) as NSFileHandleMBS

You can create a file handle for a socket by using the result of a socket call as fileDescriptor.
The object creating a file handle using this method owns fileDescriptor and is responsible for its disposition.

See also:

• fileHandleWithFileDescriptor(fd as Integer, closeOnDealloc as boolean) as NSFileHandleMBS

NSFileHandleMBS.fileHandleWithFileDescriptor(fd as Integer, closeOnDealloc as boolean) as NSFileHandleMBS

You can create a file handle for a socket by using the result of a socket call as fileDescriptor.
The object creating a file handle using this method owns fileDescriptor and is responsible for its disposition.

closeOnDealloc: True if the file descriptor should be closed when the receiver is deallocated, otherwise false.

See also:

• fileHandleWithFileDescriptor(fd as Integer) as NSFileHandleMBS

NSFileHandleMBS.fileHandleWithNullDevice as NSFileHandleMBS

You can use null-device file handles as "placeholders" for standard-device file handles or in collection objects to avoid exceptions and other errors resulting from messages being sent to invalid file handles. Read messages sent to a null-device file handle return an end-of-file indicator (an empty NSData object) rather than raise an exception. Write messages are no-ops, whereas fileDescriptor returns an illegal value. Other methods are no-ops or return "sensible" values.

NSFileHandleMBS.fileHandleWithStandardError as NSFileHandleMBS

// for GUI apps this ends on the console: (see console.app)

dim n as NSFileHandleMBS = NSFileHandleMBS.fileHandleWithStandardError

n.writeData "Hello World"

Conventionally this is a terminal device to which error messages are sent. There is one standard error file handle per process; it is a shared instance.

NSFileHandleMBS.fileHandleWithStandardInput as NSFileHandleMBS

Conventionally this is a terminal device on which the user enters a stream of data. There is one standard input file handle per process; it is a shared instance.

NSFileHandleMBS.fileHandleWithStandardOutput as NSFileHandleMBS

// for GUI apps this ends on the console: (see console.app)

dim n as NSFileHandleMBS = NSFileHandleMBS.fileHandleWithStandardOutput

n.writeData "Hello World"

Conventionally this is a terminal device that receives a stream of data from a program. There is one standard output file handle per process; it is a shared instance.

NSFileHandleMBS.NSFileHandleConnectionAcceptedNotification as string

To cause the posting of this notification, you must send either acceptConnectionInBackgroundAndNotify to an NSFileHandle object representing a server stream-type socket.
The notification object is the NSFileHandle object that sent the notification. The userInfo dictionary contains the following information:

NSFileHandleNotificationFileHandleItem	The NSFileHandle object representing the "near" end of a socket connection
NSFileHandleError	An integer representing the UNIX-type error which occurred

NSFileHandleMBS.NSFileHandleDataAvailableNotification as string

The observers can then issue the appropriate messages to begin reading the data. To cause the posting of this notification, you must send either waitForDataInBackgroundAndNotify or waitForDataInBackgroundAndNotifyForModes: to an appropriate NSFileHandle object.
The notification object is the NSFileHandle object that sent the notification. This notification does not contain a userInfo dictionary.

NSFileHandleMBS.NSFileHandleNotificationDataItem as string

The corresponding value is an memoryblock containing the available data read from a socket connection.

Some examples using this method:

• /MacBase/NSFileHandle async reading
• /MacCocoa/readToEndOfFileInBackgroundAndNotify Test

NSFileHandleMBS.NSFileHandleNotificationFileHandleItem as string

The corresponding value is the NSFileHandle object handle representing the "near" end of a socket connection.

NSFileHandleMBS.NSFileHandleNotificationMonitorModes as string

NSFileHandleMBS.NSFileHandleOperationException as string

Raised by NSFileHandle if attempts to determine file-handle type fail or if attempts to read from a file or channel fail.

NSFileHandleMBS.NSFileHandleReadCompletionNotification as string

This notification is posted when the background thread reads the data currently available in a file or at a communications channel. It makes the data available to observers by putting it in the userInfo dictionary. To cause the posting of this notification, you must send either readInBackgroundAndNotify to an appropriate NSFileHandle object.
The notification object is the NSFileHandle object that sent the notification. The userInfo dictionary contains the following information:

NSFileHandleNotificationDataItem	An string containing the available data read from a socket connection
NSFileHandleError	An integer representing the UNIX-type error which occurred

Some examples using this method:

• /MacCocoa/readToEndOfFileInBackgroundAndNotify Test

NSFileHandleMBS.NSFileHandleReadToEndOfFileCompletionNotification as string

It makes the data available to observers by putting it in the userInfo dictionary. To cause the posting of this notification, you must send either readToEndOfFileInBackgroundAndNotify to an appropriate NSFileHandle object.
The notification object is the NSFileHandle object that sent the notification. The userInfo dictionary contains the following information:

NSFileHandleNotificationDataItem: A string containing the available data read from a socket connection

NSFileHandleError

An integer representing the UNIX-type error which occurred

Some examples using this method:

• /MacBase/NSFileHandle async reading
• /MacCocoa/readToEndOfFileInBackgroundAndNotify Test