Wednesday, June 29, 2016

Command Line Argument Processing

This is another in my series of "simple programming techniques I don't want to keep reinventing."

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

int main(int argc, char**argv)
  opterr = 0; /* disable auto error reporting */
  char opt = 0;
  /* These copies are needed because optind and optarg aren't
     necessarily visible to debuggers, and you often want them. */
  int myoptind = 1;
  char* myoptarg = 0;

  int a = 0;
  const char* b = 0;

  while (((char) -1) != (opt = (char) getopt(argc, argv, "ab:"))){
    myoptind = optind;
    myoptarg = optarg;


    case 'a':
      a = 1;

    case 'b':
      b = myoptarg;

        char erropt = optopt;
        fprintf(stdout, "unrecognized option '%c'\n", erropt);

  if (myoptind < argc){
    fprintf(stdout, "unused arguments:");
    while (myoptind < argc){
      fprintf(stdout, " %s", argv[myoptind++]);
    fprintf(stdout, "\n");

  fprintf(stdout, "a: %d\nb: %s\n", a, b);
  return 0;

Saturday, January 9, 2016

Thinking about gun violence in America

This week's edition of On The Media focused -- once again -- on gun violence.

The whole show is worth listening to, but the last segment really got my attention. It's entitled, "Stopping gun violence without new laws", and it describes a program for addressing urban gun violence - a massively unreported part of the problem. OTM refers to it as CeaseFire, but it changed its name in 2012 to Cure Violence. Cure Violence treats gun violence as a public health problem, and takes a very data-driven approach to solving it. What's really great, though, is that Cure Violence offers a way to do something about guns that the NRA not only can't stop but isn't even opposed to.

They have gotten my support, and I urge you to support them, too.