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 channel
will 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 NULL
makes 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 NULL
indicates 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 GIOChannel
data 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().