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This file is part of Logtalk https://logtalk.org/ SPDX-FileCopyrightText: 2021 Paul Brown <pbrown@optimusprime.ai> SPDX-License-Identifier: Apache-2.0

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

This folder contains an example of using Tcl/Tk to provide a GUI for the symdiff example. It assumes that the logtalk_backend_select script was run to make the logtalk shell script available. If not, you will need to edit query.tcl file definition of the load_cmd variable and replace logtalk by the name of the integration script you want to use (e.g., gplgt) if using a POSIX system. On Windows, logtalk needs to be replaced by the integration shortcut command for the backend you intend to use. That command must not use any environment variables and backslashes, spaces, and square brackets must be properly escaped as per Tcl requirements.

To run the example, open the gui.tcl file using the wish application provided by your Tk installation.

This example as successfully tested with Tcl/Tk version 8.6.11 and tcllib version 1.20 on Linux and macOS. Tests on Windows have so far only worked with some backends. The issue seems to be how Windows applications handle the standard input/output streams that can break the current solution for connecting the background Logtalk process to the Tk interface for some backends.