miniargv

Lightweight cross-platform C/C++ library for processing command line arguments and displaying command line help. Support to load settings from environment variables is also included.

Features

cross-platform (tested on Windows, Linux and macOS)
low footprint (small code footprint and very low memory requirements)
no external dependencies (requires no other libraries)
zero copy approach: no memory is allocated or copied (except when reading from configuration files)
data passed to main() is processed using callback functions
- argv as passed to int main (int argc, char *argv[])
- envp as passed to int main (int argc, char *argv[], char *envp[])
values passed to callback functions live as long as main(), so no memory allocation and copying (like strdup()) needed
no cleanup functions needed before exiting the program (except when reading from configuration files)
possibility to read settings from configuration file (does require memory allocation and copying and cleanup afterwards)
partial loading of configuration file based on section
automatic generation of command line help and example configuration files with automatic formatting and line wrapping
definitions for processing and displaying help are done in a common data structure
basic error checking to report unknown arguments
does not include constraints checking (e.g. mandatory arguments or arguments that may not occur multiple times)

Documentation

Please see the online documentation (generated with Doxygen).

Installation

Download and extract the source code and use make to build and install:

make install

The default install location is /usr/local but you can override this by setting PREFIX to a different location:

make install PREFIX=/usr/custom

On Windows you can run the above commands from the MSYS2 shell using the MinGW-w64 compiler.

Example

`example.c`

#include <stdlib.h>
#include <stdio.h>
#include <miniargv.h>

int main (int argc, char *argv[], char *envp[])
{
  //variables to be configured via command line or environment
  int showhelp = 0;
  int number = 0;

  //definition of command line arguments
  const miniargv_definition argdef[] = {
    {'h', "help", NULL, miniargv_cb_increment_int, &showhelp, "show command line help", NULL},
    {'n', "number", "N", miniargv_cb_set_int, &number, "set number to N", NULL},
    MINIARGV_DEFINITION_END
  };

  //definition of environment variables
  const miniargv_definition envdef[] = {
    {0, "NUMBER", "N", miniargv_cb_set_int, &number, "set number to N", NULL},
    MINIARGV_DEFINITION_END
  };

  //parse program arguments
  if (miniargv_process(argv, envp, argdef, envdef, NULL, NULL) != 0)
    return 1;
 
  //show help if requested
  if (showhelp) {
    printf("Usage: ");
    miniargv_arg_list(argdef, 1);
    printf("\n");
    miniargv_help(argdef, envdef, 0, 0);
    return 0;
  }
 
  //show values
  printf("number = %i\n", number);
  return 0;
}

To build the example above:

gcc -o example example.c -lminiargv

Then run the example to test it:

# ./example -h
Usage: [-h] [-n N]
Command line arguments:
  -h, --help             show command line help
  -n N, --number=N       set number to N
Environment variables:
  NUMBER=N               set number to N

# ./example -n 42
number = 42

# NUMBER=64 ./example
number = 64

GitHub Actions CI

Links

The official repository can be found at: https://github.com/brechtsanders/miniargv/

The documentation can be found at: https://brechtsanders.github.io/miniargv/

License

MIT