7 Tcl/Tk Notes

Tcl/Tk itself is not included in the SICStus distribution. It must be installed in order to use the interface. It can be downloaded from the Tcl/Tk primary website:


A better alternative may be to use one of the free installers available from:


SICStus for Mac OS X uses the Tcl/Tk that comes with Mac OS X. Some versions of Tcl/Tk provided by Apple have bugs that may cause SICStus Prolog to crash when using library(tcltk). If this happens you can try to update to a newer version of Tcl/Tk from http://www.activestate.com.

The Tcl/Tk interface module included in SICStus Prolog 4.2.3 (library(tcltk)) is verified to work with Tcl/Tk 8.4, and with Tcl/Tk 8.5 for some platforms. See the SICStus download web page, http://www.sics.se/isl/sicstuswww/site/download4.html, for details.

Under UNIX, the installation program automatically detects the Tcl/Tk version (if the user does not specify it explicitly). Except as noted above, the distributed files are compiled for Tcl/Tk 8.4.

Under Windows, the binary distribution is compiled against Tcl/Tk 8.4.

Please note: You need to have the Tcl/Tk binaries accessible from your PATH environment variable, e.g. C:\Program Files\Tcl\bin.

The GUI version of SICStus, spwin, like all Windows non-console applications, lacks the C standard streams (stdin, stdout, stderr) and the Tcl command puts and others that use these streams will therefore give errors. The solution is to use sicstus instead of spwin if the standard streams are required.

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