Como library provides low manifest command line option parsing and deployment. The command line options are described in compact table format and option values are stored to conveniently named properties. Como builds command usage information based on the option table (+ generic program info) and displays it automatically if necessary. Como supports also subcommands.

A simple example program using Como:

#include <stdio.h>
#include <como.h>

int main( int argc, char** argv )
{
  como_opt_t opt;

  /* Specify program and all the options. Parsing and help is managed
     automatically. */
  como_command( "como_simple", "Programmer", "2014",
                { COMO_SINGLE, "file",  "-f", "File argument." },
                { COMO_SWITCH, "debug", "-d", "Enable debugging." }
                );

  /* Get handle of option "file". */
  opt = como_opt( "file" );

  /* Print "file" option's properties. */
  printf( "Option \"%s\" is given: %d\n", opt->name, opt->given );

  /* Print "file" option's value if option was given. */
  if ( opt->given ) {
      char** value;

      printf( "Option \"%s\" values:\n", opt->name );

      value = opt->value;
      while ( *value ) {
          printf( "  %s\n", *value );
          value++;
      }
  }

  /* Print "debug" option's "given" property. */
  printf( "Option \"%s\" is given: %d\n", "debug", como_given( "debug" ) );

  return 0;
}

You have automatically:

• -h option defined with usage printout.
• Check that -f has one and only one argument.
• Tests whether a particular option was given or not.
• Long options based on option name.
• Option values collected to an array.

Como depends on the plinth library.

Como is built with the sbin/do-build script.

Install is performed with sbin/do-install. Please, edit the script for setting the installation root directory.

The man page generation requires a2x for conversion (activate in sbin/do-build).

Manual page for Como is included in the installation (see: man/).

The source code is documented in Doxygen format. Documentation can be generated with:

doxygen .doxygen

como.h related file will include the usage information (equal to man page).

There are two simple examples in the examples/ directory: como_simple.c and como_subcmd.c.

For a complete set of features, see the test programs in test/ directory (*.c).

Ceedling based flow is in use:

shell> ceedling

Testing:

shell> ceedling test:all

User defines can be placed into project.yml. Please refer to Ceedling documentation for details.

Standard Ceedling files are not in GIT. These can be added by executing:

shell> ceedling new plinth

in the directory above Plinth. Ceedling prompts for file overwrites. You should answer NO in order to use the customized files.

See: COPYING

Como library by Tero Isannainen, (c) Copyright 2015, 2025.