LkbFaq

These FAQs concern software issues. For grammar writing issues, see the Links section at the end.

Linux

Many of the known problems are CLIM/Motif related: there's not much we can do about this as LKB developers, but there are workarounds for some problems.

1. A message about missing libraries appears when you try to start the LKB. (You may have to scan back to see this message - the apparent error may be something else.) When you start the LKB from a runtime binary, you may get an error message that says a library is missing (e.g., libXm.so.3). The CLIM interface uses Motif libraries and on some systems these are not made available by default. If you are using Solaris, you may be able to fix this by adding /usr/dt/lib to your LD_LIBRARY_PATH: if this doesn't work (or if this explanation is incomprehensible), please talk to your system administrator (it's a standard difficulty with software that uses Motif, not LKB specific). If you are using Linux, you either need to install Open Motif or to fix the installation so that the libraries are where the Lisp system expects them to be. Please see LkbInstallation.

2. The LKB interaction window appears but none of the menus work. This happens when you have lesstif installed. You will have to remove/relocate the lesstif libraries and install Open Motif.

3. The windows in the file loading interaction are incorrect sizes so it it difficult or impossible to see the file names. A known problem in CLIM and some OS versions. Fix awaited.

4. Clicking on a directory in the file loading interaction has no result. A known problem in CLIM and some OS versions. Workaround is to enter the full pathname. Fix awaited.

5. Menus suddenly freeze. Restarting the LKB does not help. If you logout and login again, the LKB menus will start to work again. Generally this problem is caused by the use of the NUMLOCK key (so it often afflicts French speakers). Workaround: don't use the NUMLOCK key when using the LKB. It's possible this problem occurs under other circumstances too - if you get this effect reproducibly without the NUMLOCK key, please send details to lkb-bugs@csli.stanford.edu

6. If emacs is shut down without quitting the LKB first, the LKB process hangs around. Known problem. Either remember to Quit the LKB before shutting down emacs or write a script to kill off errant LKBs.

Missing characters

Warnings appear about missing fonts when trying to display feature structures. The CLIM interface requires that English and iso8859-1 are set as default. If your default language uses another character set, you may need to change this.

The LKB displays a message about missing character sets (e.g., when doing Parse input) and fails. Some linux distributions appear to default to a font encoding that is incompatible with the current version of CLIM and Motif underlying the LKB run-time binaries. The problem typically surfaces when using menu commands like Parse Input where the LKB will generate an error message about Missing charsets and fail. To eliminate the problem, the system needs to be configured to use an iso8859-1 encoding instead of iso8859-15 (which, actually is just like iso8859-1 with the addition of the new Euro symbol; hence, one cannot currently use the LKB and fonts with the Euro symbol).

To set the necessary font encoding, do the following:

In RedHat, run locale_config as the super user; select a locale without the @euro suffix, say it_IT rather than it_IT@euro. As an alternative, set the value of the LANG value accordingly in in /etc/sysconfig/i18n directly.

In SuSe, run yast and perform the equivalent operation. Again, alternatively it should be sufficient to set DEFAULT_LANGUAGE in /etc/sysconfig/language and re-run yast. Unfortunately, we do not have access to a SuSe 8.x installation to test this, but LKB users have confirmed the general procedure.

Note that this is not an LKB problem, strictly speaking, but an issue with the underlying graphics toolkits (CLIM and Motif). We expect to see this resolved in future releases of the underlying software, but in the meantime hope that the loss of the Euro character will not be prohibitive to LKB users.

Windows

1. WinZip/PowerArchiver won't unpack the lkb .tgz archive correctly. We have made two versions of the Windows archive available: one .zip for WinZip (and PowerArchiver), one .tgz for tar/gzip. This problem only affects the LKB and not the grammar files.

General LKB problems

A supplied grammar gives error messages on loading or won't parse test sentences

The grammars supplied are not all mutually compatible, in the sense that if you load one grammar and then another, the new grammar may not work. So always start from a new LKB session when working with a new grammar (though grammar variants which are in a family, such as the main ITFSG grammars, can usually be loaded one after the other). In othercircumstances, if you get errors on an unmodified grammar, please email lkb-bugs@csli.stanford.edu

A grammar from a previous version of the LKB no longer works

Old grammars can generally be made to work with the current version of the LKB simply by changing the ancilliary files, user-fns and globals. If you have been working on a grammar derived from one distributed with prior versions of the LKB and you haven't changed these files, the simplest option is just to copy the files from the new version of the corresponding grammar. The next FAQ point is for people who have made changes to the user-fns files and don't want to revert back.

Defaults problem

Files written using legal TDL syntax are still loadable by the LKB without change. However, a bug in an earlier LKB version allowed an incorrect use of defaults. This shows up in one version of the textbook grammar as follows:

{{{ Syntax error at position 6368: Double defaults when reading CN-LXM

• Ignoring (part of) entry for CN-LXM Error: Syntax error(s) in type file }}}

The error is caused by the following (incorrect) definition which used to load into old versions of the LKB without complaint:

cn-lxm := noun-lxm &
[ SYN [ HEAD [ AGR #agr & [ GEND /l neut ] ],
         SPR < [ ] > ]
   ARG-ST /l < [ SYN [ HEAD det & [AGR #agr, COUNT /l true] ] ] > ].

The fix is to replace this with a correct version, without multiple defaults, for instance:

cn-lxm := noun-lxm &
 [ SYN [ HEAD [ AGR #agr & [ GEND /l neut ] ],
         SPR < [ ] > ],
   ARG-ST < [ SYN [ HEAD det & [AGR #agr, COUNT /l true] ] ] > ].

Older versions of the LKB accepted TDL definitions where a reentrancy tag was only used once. These are no longer accepted. The fix is to remove the redundant tag.

A grammar that worked with previous versions of the LKB no longer works and it is not possible to use a new version of the user-fns file

Most problems are due to a change in the LKB internal data structures which affects the user-fns file in individual grammars. In this case, the grammar will load, but there will be a Lisp error message on parsing, such as:

Error: Illegal keyword given: :TYPES.
  [condition type: PROGRAM-ERROR]

This problem is caused by a change in the function make-orth-tdfs in the user-fns file. Replace

  (make-u-value :types (list orth)) 

with

   (make-u-value :type orth)

When loading very old user-fns files, you may get error messages such as:

Warning: Free reference to undeclared variable UNIF assumed special.
Warning: Free reference to undeclared variable IN assumed special.
Warning: Free reference to undeclared variable FILTER assumed special.
Warning: While compiling these undefined functions were referenced: FOR

This is due to the use of an old for loop macro which is no longer included in the LKB. You will need to compare your user-fns file with a current version and make the appropriate changes to use the current (built-in) for loop.

The greatest lower bound introduction code leaves redundant links in place

Known LKB problem - believed fixed in 2003.

Temporary lexicons

An error such as the following may arise when loading a grammar: {{{ creating #p"/homes/aac10/tmp/templex" resulting in error: No such file or directory }}}

This is generally caused by failure to create a directory for the temporary lexicon files - see the detailed instructions. A similar error message may arise when you first try and parse a sentence for the same reason.

Similar messages may arise if your file system is full when the LKB attempt to create a temporary file.

Emacs related

There is a message from emacs when starting that it cannot find "tdl-mode" tdl-mode.el' and lkb.el' are add-on files for emacs that provide some extra functionality: structured editing of TDL files (e.g. indentation) and locate source file from the LKB. Details of how to set this up are in Using emacs with the LKB but their absence won't cause serious problems.

= Compilation = When trying to compile with Allegro Common Lisp, the following error appears: Error: "COMMON-LISP" is not the name of a package.

• [condition type: package-error]

This problem arises when one inadvertently uses a case-sensitive version of Allegro CL. Starting with 6.0 you get two versions of each binary, one typically called alisp (or alisp.exe' on Windows) for ANSI standard, one called `mlisp' which is case sensitive. Use the alisp binary instead of mlisp.

Problems compiling on a Macintosh

The LKB source files have the standard *nix end of line. If you want to compile them on a Macintosh, you may need to convert the files so that the end of line is Macintosh like. There are generally settings on ftp programs to do this.

Links

http://depts.washington.edu/uwcl/twiki/bin/view.cgi/Main/GrammarEngineeringFAQ