— Class: <gio-channel>

Opaque pointer.

This class defines no direct slots.

— Function: g-io-channel-unix-new (fd int) ⇒  (ret <gio-channel>)

Creates a new <gio-channel> given a file descriptor. On UNIX systems this works for plain files, pipes, and sockets.

The returned <gio-channel> has a reference count of 1.

The default encoding for <gio-channel> is UTF-8. If your application is reading output from a command using via pipe, you may need to set the encoding to the encoding of the current locale (see g-get-charset) with the g-io-channel-set-encoding function.

If you want to read raw binary data without interpretation, then call the g-io-channel-set-encoding function with ‘#f’ for the encoding argument.

This function is available in GLib on Windows, too, but you should avoid using it on Windows. The domain of file descriptors and sockets overlap. There is no way for GLib to know which one you mean in case the argument you pass to this function happens to be both a valid file descriptor and socket. If that happens a warning is issued, and GLib assumes that it is the file descriptor you mean.

fd

a file descriptor.

ret

a new <gio-channel>.

— Function: g-io-channel-unix-get-fd (channel <gio-channel>) ⇒  (ret int)

Returns the file descriptor of the <gio-channel>.

On Windows this function returns the file descriptor or socket of the <gio-channel>.

channel

a <gio-channel>, created with g-io-channel-unix-new.

ret

the file descriptor of the <gio-channel>.

— Function: g-io-channel-new-file (filename mchars) (mode mchars) ⇒  (ret <gio-channel>)

Open a file filename as a <gio-channel> 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).

filename

A string containing the name of a file.

mode

One of "r", "w", "a", "r+", "w+", "a+". These have the same meaning as in fopen.

error

A location to return an error of type ‘G_FILE_ERROR’.

ret

A <gio-channel> on success, ‘#f’ on failure.

— Function: g-io-channel-read-line (self <gio-channel>) ⇒  (ret <gio-status>) (string_return mchars)

Reads a line, including the terminating character(s), from a <gio-channel> into a newly-allocated string. str-return will contain allocated memory if the return is ‘G_IO_STATUS_NORMAL’.

channel

a <gio-channel>

str-return

The line read from the <gio-channel>, including the line terminator. This data should be freed with g-free when no longer needed. This is a nul-terminated string. If a length of zero is returned, this will be ‘#f’ instead.

length

location to store length of the read data, or ‘#f’

terminator-pos

location to store position of line terminator, or ‘#f’

error

A location to return an error of type <g-convert-error> or <gio-channel-error>

ret

the status of the operation.

— Function: g-io-channel-flush (channel <gio-channel>) ⇒  (ret <gio-status>)

Flushes the write buffer for the GIOChannel.

channel

a <gio-channel>

error

location to store an error of type <gio-channel-error>

ret

the status of the operation: One of <g-io-channel-normal>, <g-io-channel-again>, or <g-io-channel-error>.

— Function: g-io-channel-seek-position (self <gio-channel>) (offset int64) (type <g-seek-type>) ⇒  (ret <gio-status>)

Replacement for g-io-channel-seek with the new API.

channel

a <gio-channel>

offset

The offset in bytes from the position specified by type

type

a <g-seek-type>. The type ‘G_SEEK_CUR’ is only allowed in those cases where a call to g-io-channel-set-encoding is allowed. See the documentation for g-io-channel-set-encoding for details.

error

A location to return an error of type <gio-channel-error>

ret

the status of the operation.

— Function: g-io-channel-shutdown (channel <gio-channel>) (flush bool) ⇒  (ret <gio-status>)

Close an IO channel. Any pending data to be written will be flushed if flush is ‘#t’. The channel will not be freed until the last reference is dropped using g-io-channel-unref.

channel

a <gio-channel>

flush

if ‘#t’, flush pending

err

location to store a <gio-channel-error>

ret

the status of the operation.

— Function: g-io-channel-error-from-errno (en int) ⇒  (ret <gio-channel-error>)

Converts an ‘errno’ error number to a <gio-channel-error>.

en

an ‘errno’ error number, e.g. ‘EINVAL’.

ret

a <gio-channel-error> error number, e.g. ‘G_IO_CHANNEL_ERROR_INVAL’.

— Function: g-io-create-watch (channel <gio-channel>) (condition <gio-condition>) ⇒  (ret <g-source>)

Creates a <g-source> that's dispatched when condition is met for the given channel. For example, if condition is <g-io-in>, the source will be dispatched when there's data available for reading. g-io-add-watch is a simpler interface to this same functionality, for the case where you want to add the source to the default main loop at the default priority.

On Windows, polling a <g-source> created to watch a channel for a socket puts the socket in non-blocking mode. This is a side-effect of the implementation and unavoidable.

channel

a <gio-channel> to watch

condition

conditions to watch for

ret

a new <g-source>

— Function: g-io-add-watch (channel <gio-channel>) (condition <gio-condition>) (func scm) ⇒  (ret bool)

Adds the <gio-channel> into the main event loop with the default priority.

channel

a <gio-channel>.

condition

the condition to watch for.

func

the function to call when the condition is satisfied.

user-data

user data to pass to func.

ret

the event source id.

— Function: g-io-channel-get-buffer-size (channel <gio-channel>) ⇒  (ret size_t)

Gets the buffer size.

channel

a <gio-channel>

ret

the size of the buffer.

— Function: g-io-channel-set-buffer-size (channel <gio-channel>) (size size_t)

Sets the buffer size.

channel

a <gio-channel>

size

the size of the buffer. 0 == pick a good size

— Function: g-io-channel-get-buffer-condition (channel <gio-channel>) ⇒  (ret <gio-condition>)

This function returns a <gio-condition> depending on whether there is data to be read/space to write data in the internal buffers in the <gio-channel>. Only the flags ‘G_IO_IN’ and ‘G_IO_OUT’ may be set.

channel

A <gio-channel>

ret

A <gio-condition>

— Function: g-io-channel-get-flags (channel <gio-channel>) ⇒  (ret <gio-flags>)

Gets the current flags for a <gio-channel>, including read-only flags such as ‘G_IO_FLAG_IS_READABLE’.

The values of the flags ‘G_IO_FLAG_IS_READABLE’ and ‘G_IO_FLAG_IS_WRITEABLE’ are cached for internal use by the channel when it is created. If they should change at some later point (e.g. partial shutdown of a socket with the UNIX shutdown function), the user should immediately call g-io-channel-get-flags to update the internal values of these flags.

channel

a <gio-channel>

ret

the flags which are set on the channel

— Function: g-io-channel-set-flags (channel <gio-channel>) (flags <gio-flags>) ⇒  (ret <gio-status>)

Sets the (writeable) flags in channel to (flags & ‘G_IO_CHANNEL_SET_MASK’).

channel

a <gio-channel>.

flags

the flags to set on the IO channel.

error

A location to return an error of type <gio-channel-error>.

ret

the status of the operation.

— Function: g-io-channel-get-line-term (channel <gio-channel>) ⇒  (ret mchars) (length int)

This returns the string that <gio-channel> uses to determine where in the file a line break occurs. A value of ‘#f’ indicates auto detection.

channel

a <gio-channel>

length

a location to return the length of the line terminator

ret

The line termination string. This value is owned by GLib and must not be freed.

— Function: g-io-channel-set-line-term (channel <gio-channel>) (line_term mchars) (length int)

This sets the string that <gio-channel> uses to determine where in the file a line break occurs.

channel

a <gio-channel>

line-term

The line termination string. Use ‘#f’ for auto detect. Auto detection breaks on "\n", "\r\n", "\r", "\0", and the Unicode paragraph separator. Auto detection should not be used for anything other than file-based channels.

length

The length of the termination string. If -1 is passed, the string is assumed to be nul-terminated. This option allows termination strings with embeded nuls.

— Function: g-io-channel-get-buffered (channel <gio-channel>) ⇒  (ret bool)

Returns whether channel is buffered.

channel

a <gio-channel>.

ret

‘#t’ if the channel is buffered.

— Function: g-io-channel-set-buffered (channel <gio-channel>) (buffered bool)

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

A buffered channel can only be set unbuffered if the channel's internal buffers have been flushed. Newly created channels or channels which have returned ‘G_IO_STATUS_EOF’ not require such a flush. For write-only channels, a call to g-io-channel-flush is sufficient. For all other channels, the buffers may be flushed by a call to g-io-channel-seek-position. This includes the possibility of seeking with seek type ‘G_SEEK_CUR’ and an offset of zero. Note that this means that socket-based channels cannot be set unbuffered once they have had data read from them.

On unbuffered channels, it is safe to mix read and write calls from the new and old APIs, if this is necessary for maintaining old code.

The default state of the channel is buffered.

channel

a <gio-channel>

buffered

whether to set the channel buffered or unbuffered

— Function: g-io-channel-get-encoding (channel <gio-channel>) ⇒  (ret mchars)

Gets the encoding for the input/output of the channel. The internal encoding is always UTF-8. The encoding ‘#f’ makes the channel safe for binary data.

channel

a <gio-channel>

ret

A string containing the encoding, this string is owned by GLib and must not be freed.

— Function: g-io-channel-set-encoding (channel <gio-channel>) (encoding mchars) ⇒  (ret <gio-status>)

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.

The encoding ‘#f’ is safe to use with binary data.

The encoding can only be set if one of the following conditions is true:

1. The channel was just created, and has not been written to or read from yet.

2. The channel is write-only.

3. The channel is a file, and the file pointer was just repositioned by a call to g-io-channel-seek-position. (This flushes all the internal buffers.)

4. The current encoding is ‘#f’ or UTF-8.

5. One of the (new API) read functions has just returned ‘G_IO_STATUS_EOF’ (or, in the case of g-io-channel-read-to-end, ‘G_IO_STATUS_NORMAL’).

6. One of the functions g-io-channel-read-chars or g-io-channel-read-unichar has returned ‘G_IO_STATUS_AGAIN’ or ‘G_IO_STATUS_ERROR’. This may be useful in the case of ‘G_CONVERT_ERROR_ILLEGAL_SEQUENCE’. Returning one of these statuses from g-io-channel-read-line, g-io-channel-read-line-string, or g-io-channel-read-to-end does not guarantee that the encoding can be changed.

Channels which do not meet one of the above conditions cannot call g-io-channel-seek-position with an offset of ‘G_SEEK_CUR’, and, if they are "seekable", cannot call g-io-channel-write-chars after calling one of the API "read" functions.

channel

a <gio-channel>

encoding

the encoding type

error

location to store an error of type <g-convert-error>.

ret

‘G_IO_STATUS_NORMAL’ if the encoding was successfully set.

— Function: g-io-channel-close (channel <gio-channel>)

‘g_io_channel_close’ has been deprecated since version 2.2 and should not be used in newly-written code. Use g-io-channel-shutdown instead.

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.

channel

A <gio-channel>