LNT2LOTOS manual page
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lnt2lotos - LNT to LOTOS translator


lnt2lotos [-silent | -verbose] [-version] [-force] [-more command] [-pidlist] [-root instantiation] filename[.lnt]


LNT (LOTOS New Technology, formerly noted LOTOS NT) is an imperatively styled specification language for concurrent processes. The lnt2lotos program translates a LNT specification to a LOTOS specification.

The input to lnt2lotos is a LNT file, which must have the extension .lnt. If the user does not specify the extension .lnt on the command line, it will be appended automatically and lnt2lotos will read filename.lnt as input. External C code can be provided by auxiliary files, namely filename.tnt for data type definitions and filename.fnt for function definitions.

Typically, the input should have been pre-processed by lpp before being passed to lnt2lotos. The pre-processor expands extended notation such as literal numbers and strings, which is not accepted by lnt2lotos directly.

The principal output of lnt2lotos is a LOTOS specification named filename.lotos (unless the -root null option is used, in which case a LOTOS library FILENAME.lib is generated instead; see below for further details). Two auxiliary files are also generated, namely filename.t, which contains C code for external data types, and filename.f, which contains C code for external functions. Note that filename.t includes filename.tnt (if present), and that filename.f includes filename.fnt (if present).

To avoid confusion between source code and generated code, all output files created by lnt2lotos will be placed in a special directory that lnt2lotos creates if it does not exist already. If the creation of the directory fails, lnt2lotos issues an error message and stops. The name of this directory is either given by the environment variable $LNTGEN, if this variable is set, or is ./LNTGEN by default. Note that ./LNTGEN (or $LNTGEN) is created relative to the directory from which the user calls lnt2lotos, not relative to the directory containing the input file.

The name of the input file is used to construct the names of the output files, with the particular rule that all letters are turned to upper case when constructing the names of .lib files. For an input file example.lnt, lnt2lotos creates the LOTOS library EXAMPLE.lib or the LOTOS specification example.lotos, and two auxiliary files example.t and example.f. To avoid clashes between generated files and user-written files, lnt2lotos writes a special tag at the beginning of each generated file. This tag is a comment containing the name and the version of lnt2lotos that generated the file. lnt2lotos uses this tag for two purposes:


Execute silently, reporting only errors. This is the opposite of -verbose. The default option is -verbose.

Report activities and progress, including errors, to the user's screen. This is the opposite of -silent. The default option is -verbose.

Display the tool version and exit.

Overwrite the output files, even if they were edited by the user or do not need to be updated.

-more command
Use command to display the error messages, instead of "$CADP/src/com/cadp_more", which is the default. command is a shell command (preferably enclosed in quotes or double quotes) containing the pathname of the chosen pager, possibly followed by a list of options. Not a default option.

List the names of all processes without value parameters that occur in the input file and exit. In other words, list all processes that can be used as main process (by instantiation with the -root option).

-root instantiation
where instantiation can take three different forms: module, null, or a character string of the form "P [G1, ..., Gm] (V1, ..., Vn)" according to the syntax for a process instantiation given in the reference manual [Champelovier-Clerc-Garavel-et-al-10]. By default, if the "-root" option is absent, it is assumed to be of the third form and identical to "-root MAIN".
If the option "-root module" is specified, lnt2lotos will generate a LOTOS library (i.e., a ".lib" file without main behaviour). If the LNT specification contains a process called MAIN, it will be treated like an ordinary process.
If the option "-root null" is specified, lnt2lotos will generate a LOTOS specification whose main behaviour is "stop". If the LNT specification contains a process called MAIN, it will be treated like an ordinary process.
In the third case, lnt2lotos will generate a LOTOS specification whose main behaviour is the instantiation of process P with actual gate identifiers [G1, ..., Gm] and actual value parameters (V1, ..., Vn).
As processes cannot be overloaded in LNT, there must be at most one process called P in the LNT specification, either directly defined in filename.lnt or defined in a included module included transitively.
The list of actual gate parameters is optional; if this list is missing and if filename.lnt does not contain a process named P, an empty list of gate parameters is assumed; if this list is missing and if filename.lnt contains a process named P, lnt2lotos will replace a missing list of actual gate parameters by the list of formal gate parameters of the process P. If process P is defined in filename.lnt, the list of actual gate parameters can also be given using named-style parameters (``=>'') and ellipses (``...'').
The list of actual value parameters is also optional; if this list is missing, an empty list of value parameters is assumed. It should only contain algebraically-closed terms (i.e., contain no variables) and be compatible, in number and types, with the list of formal variable parameters of process P. Process P should have only in parameters (i.e., no out or inout parameter). If the actual value parameters use rich-term syntax notations [Champelovier-Clerc-Garavel-et-al-10, chapter 3], these notations must be expanded before invoking lnt2lotos; this is automatically performed by lnt.open which calls lpp to expand rich-term syntax before invoking lnt2lotos.


LNT specification (input)

C code for data types (input)

C code for functions (input)

imported modules signatures (input)

LOTOS code (optional output)

LOTOS code (optional output)

C code (output)

C code (output)

detailed error messages (output)

module signature (output)


LNT predefined library (LOTOS code)

LNT predefined library (C code)

Environment Variables

The target directory of the output files.

Exit Status

If the translation was successful the exit status is 0, even if warnings were issued during the execution. If any error occurred during translation, the exit status is 1.


David Champelovier, Xavier Clerc, Hubert Garavel, Gideon Smeding, Frederic Lang, Wendelin Serwe (INRIA Rhone-Alpes)

See Also

caesar.adt , caesar , lotos , lnt.open , lpp , and the "Reference Manual of the LNT to LOTOS Translator" available from http://cadp.inria.fr/publications/Champelovier-Clerc-Garavel-et-al-10.html

Additional information is available from the CADP Web page located at http://cadp.inria.fr

Directives for installation are given in files $CADP/INSTALLATION_*.

Recent changes and improvements to this software are reported and commented in file $CADP/HISTORY.


The type system of lnt2lotos is not implemented in full detail, hence, some incorrect LNT programs will be accepted by lnt2lotos and translated into LOTOS. However, these errors will be detected by the LOTOS compilers caesar and caesar.adt. Please report any mistranslations or other problems with lnt2lotos to cadp@inria.fr

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