OutputStream

Object Hierarchy:

Description:

[ CCode ( type_id = "g_output_stream_get_type ()" ) ]
public abstract class OutputStream : Object

`GOutputStream` is a base class for implementing streaming output.

It has functions to write to a stream ([method@Gio.OutputStream.write]), to close a stream ([method@Gio.OutputStream.close]) and to flush pending writes ([method@Gio.OutputStream.flush]).

To copy the content of an input stream to an output stream without manually handling the reads and writes, use [method@Gio.OutputStream.splice] .

See the documentation for [class@Gio.IOStream] for details of thread safety of streaming APIs.

All of these functions have async variants too.

All classes derived from `GOutputStream` *should* implement synchronous writing, splicing, flushing and closing streams, but *may* implement asynchronous versions.

Example: IOStream:

public static int main (string[] args) {
	try {
		// Create a file that can only be accessed by the current user:
		File file = File.new_for_path ("my-test.bin");
		IOStream ios = file.create_readwrite (FileCreateFlags.PRIVATE);


		//
		// Write data:
		//

		size_t bytes_written;
		OutputStream os = ios.output_stream;
		os.write_all ("My 1. line\n".data, out bytes_written);
		os.write_all ("My 2. line\n".data, out bytes_written);

		DataOutputStream dos = new DataOutputStream (os);
		dos.put_string ("My 3. line\n");
		dos.put_int16 (10);
		ios = null;


		// Open the file for reading:
		InputStream @is = file.read ();


		//
		// Read n bytes:
		//

		// Output: ``M``
		uint8 buffer[1];
		size_t size = @is.read (buffer);
		stdout.write (buffer, size);

		// Output: ``y 1. line``
		DataInputStream dis = new DataInputStream (@is);
		string str = dis.read_line ();
		print ("%s\n", str);

		// Output: ``My 2. line``
		str = dis.read_line ();
		print ("%s\n", str);

		// Output: ``My 3. line``
		str = dis.read_line ();
		print ("%s\n", str);

		// Output: ``10``
		int16 i = dis.read_int16 ();
		print ("%d\n", i);
	} catch (Error e) {
		print ("Error: %s\n", e.message);
	}

	return 0;
}

valac --pkg gio-2.0 GLib.IOStream.vala

All known sub-classes:

Required by:

PollableOutputStream

Namespace: GLib

Package: gio-2.0

Content:

Creation methods:

protected OutputStream ()

Methods:

public void clear_pending ()
Clears the pending flag on this.
public abstract bool close (Cancellable? cancellable = null) throws IOError
Closes the stream, releasing resources related to it.
public virtual async bool close_async (int io_priority = DEFAULT, Cancellable? cancellable = null) throws IOError
Requests an asynchronous close of the stream, releasing resources related to it.
public virtual bool flush (Cancellable? cancellable = null) throws Error
Forces a write of all user-space buffered data for the given this.
public virtual async bool flush_async (int io_priority = DEFAULT, Cancellable? cancellable = null) throws Error
Forces an asynchronous write of all user-space buffered data for the given this.
public bool has_pending ()
Checks if an output stream has pending actions.
public bool is_closed ()
Checks if an output stream has already been closed.
public bool is_closing ()
Checks if an output stream is being closed.
public bool printf (out size_t bytes_written, Cancellable? cancellable, string format, ...) throws Error
This is a utility function around write_all.
public bool set_pending () throws Error
Sets this to have actions pending.
public virtual ssize_t splice (InputStream source, OutputStreamSpliceFlags flags, Cancellable? cancellable = null) throws IOError
Splices an input stream into an output stream.
public virtual async ssize_t splice_async (InputStream source, OutputStreamSpliceFlags flags, int io_priority = DEFAULT, Cancellable? cancellable = null) throws IOError
Splices a stream asynchronously.
public bool vprintf (out size_t bytes_written, Cancellable? cancellable, string format, va_list args) throws Error
This is a utility function around write_all.
public abstract ssize_t write (uint8[] buffer, Cancellable? cancellable = null) throws IOError
Tries to write buffer.length bytes from buffer into the stream.
public bool write_all (uint8[] buffer, out size_t bytes_written, Cancellable? cancellable = null) throws IOError
Tries to write buffer.length bytes from buffer into the stream.
public async bool write_all_async (uint8[] buffer, int io_priority, Cancellable? cancellable, out size_t bytes_written) throws Error
Request an asynchronous write of buffer.length bytes from buffer into the stream.
public virtual async ssize_t write_async (uint8[]? buffer, int io_priority = DEFAULT, Cancellable? cancellable = null) throws IOError
Request an asynchronous write of buffer.length bytes from buffer into the stream.
public ssize_t write_bytes (Bytes bytes, Cancellable? cancellable = null) throws Error
A wrapper function for write which takes a Bytes as input.
public async ssize_t write_bytes_async (Bytes bytes, int io_priority = DEFAULT, Cancellable? cancellable = null) throws Error
This function is similar to write_async, but takes a Bytes as input.
public virtual bool writev (OutputVector[] vectors, out size_t bytes_written, Cancellable? cancellable = null) throws Error
Tries to write the bytes contained in the vectors.length vectors into the stream.
public bool writev_all (OutputVector[] vectors, out size_t bytes_written, Cancellable? cancellable = null) throws Error
Tries to write the bytes contained in the vectors.length vectors into the stream.
public async bool writev_all_async (OutputVector[] vectors, int io_priority = DEFAULT, Cancellable? cancellable = null, out size_t bytes_written) throws Error
Request an asynchronous write of the bytes contained in the vectors.length vectors into the stream.
public virtual async bool writev_async (OutputVector[] vectors, int io_priority = DEFAULT, Cancellable? cancellable = null, out size_t bytes_written) throws Error
Request an asynchronous write of the bytes contained in vectors.length vectors into the stream.

Inherited Members:

All known members inherited from class GLib.Object