GLib.IOChannel (original) (raw)

Struct

GLibIOChannel

Description [src]

struct GIOChannel {
  /* No available fields */
}

The GIOChannel data type aims to provide a portable method for using file descriptors, pipes, and sockets, and integrating them into the main event loop (see GMainContext). Currently, full support is available on UNIX platforms; support for Windows is only partially complete.

To create a new GIOChannel on UNIX systems useg_io_channel_unix_new(). This works for plain file descriptors, pipes and sockets. Alternatively, a channel can be created for a file in a system independent manner using g_io_channel_new_file().

Once a GIOChannel has been created, it can be used in a generic manner with the functions g_io_channel_read_chars(),g_io_channel_write_chars(), g_io_channel_seek_position(), and g_io_channel_shutdown().

To add a GIOChannel to the main event loop, use g_io_add_watch() org_io_add_watch_full(). Here you specify which events you are interested in on the GIOChannel, and provide a function to be called whenever these events occur.

GIOChannel instances are created with an initial reference count of 1.g_io_channel_ref() and g_io_channel_unref() can be used to increment or decrement the reference count respectively. When the reference count falls to 0, the GIOChannel is freed. (Though it isn’t closed automatically, unless it was created usingg_io_channel_new_file().) Using g_io_add_watch() org_io_add_watch_full() increments a channel’s reference count.

The new functions g_io_channel_read_chars(),g_io_channel_read_line(), g_io_channel_read_line_string(),g_io_channel_read_to_end(), g_io_channel_write_chars(),g_io_channel_seek_position(), and g_io_channel_flush()should not be mixed with the deprecated functionsg_io_channel_read(), g_io_channel_write(), andg_io_channel_seek() on the same channel.

Constructors

g_io_channel_new_file

Open a file filename as a GIOChannel using mode mode. This channel will be closed when the last reference to it is dropped, so there is no need to call g_io_channel_close() (though doing so will not cause problems, as long as no attempt is made to access the channel after it is closed).

g_io_channel_unix_new

Creates a new GIOChannel given a file descriptor. On UNIX systems this works for plain files, pipes, and sockets.

Functions

Instance methods

g_io_channel_close

Close an IO channel. Any pending data to be written will be flushed, ignoring errors. The channel will not be freed until the last reference is dropped using g_io_channel_unref().

deprecated: 2.2

g_io_channel_get_buffer_condition

This function returns a GIOCondition depending on whether there is data to be read/space to write data in the internal buffers in the GIOChannel. Only the flags G_IO_IN and G_IO_OUT may be set.

g_io_channel_get_close_on_unref

Returns whether the file/socket/whatever associated with channelwill be closed when channel receives its final unref and is destroyed. The default value of this is TRUE for channels created by g_io_channel_new_file (), and FALSE for all other channels.

g_io_channel_get_encoding

Gets the encoding for the input/output of the channel. The internal encoding is always UTF-8. The encoding NULLmakes the channel safe for binary data.

g_io_channel_get_flags

Gets the current flags for a GIOChannel, including read-only flags such as G_IO_FLAG_IS_READABLE.

g_io_channel_get_line_term

This returns the string that GIOChannel uses to determine where in the file a line break occurs. A value of NULLindicates autodetection. Since 2.84, the return value is always nul-terminated.

g_io_channel_read_line

Reads a line, including the terminating character(s), from a GIOChannel into a newly-allocated string.str_return will contain allocated memory if the return is G_IO_STATUS_NORMAL.

g_io_channel_read_unichar

Reads a Unicode character from channel. This function cannot be called on a channel with NULL encoding.

g_io_channel_seek

Sets the current position in the GIOChannel, similar to the standard library function fseek().

deprecated: 2.2

g_io_channel_set_buffered

The buffering state can only be set if the channel’s encoding is NULL. For any other encoding, the channel must be buffered.

g_io_channel_set_close_on_unref

Whether to close the channel on the final unref of the GIOChanneldata structure. The default value of this is TRUE for channels created by g_io_channel_new_file (), and FALSE for all other channels.

g_io_channel_set_encoding

Sets the encoding for the input/output of the channel. The internal encoding is always UTF-8. The default encoding for the external file is UTF-8.

g_io_channel_shutdown

Close an IO channel. Any pending data to be written will be flushed if flush is TRUE. The channel will not be freed until the last reference is dropped using g_io_channel_unref().