NSPipe Class Reference
| Inherits from | |
| Conforms to | |
| Framework | /System/Library/Frameworks/Foundation.framework |
| Availability | Available in OS X v10.0 and later. |
| Companion guide | Interacting with the Operating System |
| Declared in | NSFileHandle.h |
Overview
NSPipe objects provide an object-oriented interface for accessing pipes. An NSPipe object represents both ends of a pipe and enables communication through the pipe. A pipe is a one-way communications channel between related processes; one process writes data, while the other process reads that data. The data that passes through the pipe is buffered; the size of the buffer is determined by the underlying operating system. NSPipe is an abstract class, the public interface of a class cluster.
Class Methods
pipe
Returns an NSPipe object.
Return Value
An initialized NSPipe object. Returns nil if the method encounters errors while attempting to create the pipe or the NSFileHandle objects that serve as endpoints of the pipe.
Availability
- Available in OS X v10.0 and later.
Declared In
NSFileHandle.hInstance Methods
fileHandleForReading
Returns the receiver's read file handle.
Return Value
The receiver's read file handle.The descriptor represented by this object is deleted, and the object itself is automatically deallocated when the receiver is deallocated.
Discussion
You use the returned file handle to read from the pipe using NSFileHandle's read methods—availableData, readDataToEndOfFile, and readDataOfLength:.
You don’t need to send closeFile to this object or explicitly release the object after you have finished using it.
Availability
- Available in OS X v10.0 and later.
Declared In
NSFileHandle.hfileHandleForWriting
Returns the receiver's write file handle.
Return Value
The receiver's write file handle. This object is automatically deallocated when the receiver is deallocated.
Discussion
You use the returned file handle to write to the pipe using NSFileHandle's writeData: method. When you are finished writing data to this object, send it a closeFile message to delete the descriptor. Deleting the descriptor causes the reading process to receive an end-of-data signal (an empty NSData object).
Availability
- Available in OS X v10.0 and later.
Declared In
NSFileHandle.hinit
Returns an initialized NSPipe object.
Return Value
An initialized NSPipe object. Returns nil if the method encounters errors while attempting to create the pipe or the NSFileHandle objects that serve as endpoints of the pipe.
Availability
- Available in OS X v10.0 and later.
See Also
Declared In
NSFileHandle.h© 2007 Apple Inc. All Rights Reserved. (Last updated: 2007-01-26)