Gio.DataInputStream.prototype.read_line_utf8

function read_line_utf8(cancellable: Gio.Cancellable): [return_value: String, length: Number(gsize)] {
    // Gjs wrapper for g_data_input_stream_read_line_utf8()
}

Reads a UTF-8 encoded line from the data input stream.

If cancellable is not null, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error Gio.IOErrorEnum.cancelled will be returned.

Since 2.30

cancellable: optional Gio.Cancellable object, null to ignore.
return_value: a NUL terminated UTF-8 string with the line that was read in (without the newlines). Set length to a #gsize to get the length of the read line. On an error, it will return null and @error will be set. For UTF-8 conversion errors, the set error domain is %G_CONVERT_ERROR. If there's no content to read, it will still return null, but @error won't be set.
length: a #gsize to get the length of the data read in.