NAME

       lopsub - Long option parser for subcommands

About

       Lopsub  is  an  open source library written in C which aims to ease the task of creating, documenting and
       parsing the options of Unix command line utilities. It is suitable for simple commands as well as complex
       command line utilities with many subcommands where each subcommand has its own set  of  options.  Options
       and documentation are kept together in a single file which can be translated to C code (to be included in
       the application), or to a manual page.  The library supports single-character short options and GNU-style
       long options. The public API is well documented and stable.

       To make use of the library, the programmer provides a so-called suite file which describes the options of
       the  application  in  an  intuitive syntax. At build time the suite file is translated into C code by the
       lopsubgen utility which also ships with the lopsub package. The generated code defines an instance of  an
       opaque  C structure and exposes a reference to this structure which can be passed to the option parser at
       run time, together with the usual argument vector. The option parser is part of the  lopsub  library,  so
       applications  need to link with -llopsub.  In addition to the option parser, the library offers many more
       features. For example, there is a function for  merging  two  different  parse  results  to  generate  an
       effective  configuration.  This  is  useful for applications which can be configured through command line
       options and via a config file.

       The suite file can also be processed into roff format to create a manual page. Conversion into  html  can
       easily be performed with tools like grohtml (part of GNU roff) or man2html.

       Lopsub  does  not  rely  on the system's getopt() or getopt_long() functions of the C library and is thus
       portable across different flavors of Unix. It is known to work on Linux, NetBSD and FreeBSD.

License

       The lopsub library is licensed under the LGPLv3 while the lopsubgen utility is licensed under the  GPLv3.
       The  examples  and all code generated by the utilities, however, is licensed under the public domain. You
       are free to do anything you like with the generated code, including incorporating it into or  linking  it
       with proprietary software.

Quick Start

       Compile  and  run  the  minimal  example  included at the end of lopsub-suite(5).  Examine lopsubex.c and
       lopsubex.suite in the source tree and run the lopsubex command.

API documentation

       See ./lopsub-api.html.  Alternatively, examine lopsub.h or lopsub.h.m4.

Resources

       • git clone URL: https://git.tuebingen.mpg.de/lopsub.git

       • gitweb: https://git.tuebingen.mpg.de/lopsub.git

       • The author's homepage: https://people.tuebingen.mpg.de/maan/

       • Send feedback to Andre Noll

1.0.5                                               May 2024                                           lopsub(7)