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FileDescriptor.Sync Method

Definition

Force all system buffers to synchronize with the underlying device.

[Android.Runtime.Register("sync", "()V", "")]
public void Sync ();
[<Android.Runtime.Register("sync", "()V", "")>]
member this.Sync : unit -> unit
Attributes

Exceptions

Remarks

Force all system buffers to synchronize with the underlying device. This method returns after all modified data and attributes of this FileDescriptor have been written to the relevant device(s). In particular, if this FileDescriptor refers to a physical storage medium, such as a file in a file system, sync will not return until all in-memory modified copies of buffers associated with this FileDescriptor have been written to the physical medium.

sync is meant to be used by code that requires physical storage (such as a file) to be in a known state For example, a class that provided a simple transaction facility might use sync to ensure that all changes to a file caused by a given transaction were recorded on a storage medium.

sync only affects buffers downstream of this FileDescriptor. If any in-memory buffering is being done by the application (for example, by a BufferedOutputStream object), those buffers must be flushed into the FileDescriptor (for example, by invoking OutputStream.flush) before that data will be affected by sync.

Added in JDK1.1.

Java documentation for java.io.FileDescriptor.sync().

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to