Overview

The so-called LOGON distribution (please see the LogonTop page, for general background) includes pre-compiled binaries of the PET parsing system. To support a variety of user needs, there are binaries for a range of different configurations, ‘hidden’ behind wrapper scripts that provide a command-line option, to select a specific binary. Furthermore, the scripts prepare the run-time environment for the pre-compiled binaries, specifically set up the dynamic linker search path ($LD_LIBRARY_PATH) temporarily, to make sure the binary finds all its required libraries (in the right versions). Note that, as of mid-2011, the actual LOGON PET binaries always run in 32-bit mode (even on a 64-bit Linux installation), hence make sure to have 32-bit compatibility mode installed (the default on RedHat Linux and derivatives, though apparently not necessarily so on recent Ubuntu distributions).

The LOGON front-ends to the two PET components are $LOGONROOT/bin/flop and $LOGONROOT/bin/cheap, which will be automatically added to the shell search path (the $PATH environment variable) in a functional LOGON installation (please work through the LogonInstallation page, in case the above does not seem true in your case). In contrast to the standard PET binaries, the LOGON wrappers take one additional command-line option, which furthermore /must/ be provided as the very first option, right after the command name. When omitted, the wrapper will default on the current ‘trunk’ revision of the PET binaries (see below for details).

For example, the following command will invoke the ‘stable’ (see below) version of the PET grammar compiler, flop:

  flop --stable english.tdl

Conversely, to run the bleeding-edge ‘testing’ (see below) version of the PET parser (cheap), one could issue a command like the following:

  cheap --test -repp -tagger -cm -default-les=all english.grm

In either case, all command-line arguments but the first are passed verbatim to the actual binary.

Supported Configurations

As of mid-2011, there are three available PET configurations in the LOGON tree proper, plus some support for locally compiled binaries, external to the LOGON tree.

The stable PET binaries support users who require PET functionality as of around the first half of 2010 (e.g. prior to the addition of native REPP support). These binaries are compiled off the so-called legacy branch (which in mid-2011 corresponds to the 1.0 release version of PET, though may over time have critical fixes back-ported to it) and will continue (at least for the foreseeable future) to provide functionality that in around 2010 was judged deprecated by the PET developers and is thus not actively supported (and likely to disappear in newer versions; please see the PET mailing list for details). Stable flop and cheap binaries, in the LOGON tree, are activated through the –stable option to the wrapper scripts.

Bleeding-edge testing versions, on the other hand, may not always be available and will typically target a small sub-community of ‘power’ users and PET or LOGON co-developers. It is typically compiled off an active branch (e.g. the next generation, or NG, branch in mid-2011) and should typically not be used for regular development, at least not without close communication with the PET developer(s) on the branch in question. Unlike the stable binaries, testing binaries may or may not include ECL. Testing flop and cheap binaries are activated through the –test command-line option.

Finally, the default binaries should be suitable for regular users; they are compiled off the PET development trunk (called main), with quality control by the LOGON developers (and users). Typically, these binaries will reflect the head revision of the trunk, although for practical (lack of time) or contentful reasons (a critical known issue, yet to be resolved) may lag behind trunk development some. Default binaries are activated when the flop and cheap wrappers are called without an extra initial argument, e.g. (mirroring an earlier example):

  cheap -repp -tagger -cm -default-les=all english.grm

PET Developer Support

In addition to the three configurations above, the LOGON flop and cheap wrapper scripts provide some limited support for running a user-provided (locally compiled) binary. These are activated by the –local option; please see the source code for further information (or contact StephanOepen directly). Furthermore, the selection of a specific cheap configuration can be short-circuited by virtue of the $LOGONCHEAP environment variable (in which case, no extra command-line option must be supplied), e.g.

  LOGONCHEAP=~/src/pet/repp/debug/cheap/cheap \
    cheap -repp -tagger -cm -default-les=all -timeout=60 english.grm

This facility will be most useful (if at all), when running cheap through LOGON batch processing scripts; please see the LogonProcessing/BatchParsing page, for further discussion.

Implementation Notes

As of mid-2011, PET binaries are compiled in the standard LOGON build environment, a 32-bit CentOS 4.9 distribution. The actual binaries reside in $LOGONROOT/uio/bin/linux.x86.32, with associated shared libraries in $LOGONROOT/uio/lib/linux.x86.32.

Last update: 2021-06-18 by Alexandre Rademaker [edit]