popt.c

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#include <popt.h>
#include <stdio.h>

void usage (poptContext optCon, int exitcode, char *error, char *addl)
{
   poptPrintUsage (optCon, stderr, 0);
   
   if (error) fprintf (stderr, "%s: %s", error, addl);
   
   exit (exitcode);
}

int main (int argc, char *argv[]) {
  char    c;            /* used for argument parsing */
  int     i = 0;        /* used for tracking options */
  char    *portname;
  int     speed = 0;    /* used in argument parsing to set speed */
  int     raw = 0;      /* raw mode? */
  int     j;
  char    buf[BUFSIZ+1];
  poptContext optCon;   /* context for parsing command-line options */

  struct poptOption optionsTable[] = {
                  { "bps", 'b', POPT_ARG_INT, &speed, 0,
                    "signaling rate in bits-per-second", "BPS" },
                  { "crnl", 'c', 0, 0, 'c',
                    "expand cr characters to cr/lf sequences" },
                  { "hwflow", 'h', 0, 0, 'h',
                    "use hardware (RTS/CTS) flow control" },
                  { "noflow", 'n', 0, 0, 'n',
                    "use no flow control" },
                  { "raw", 'r', 0, &raw, 0,
                    "don't perform any character conversions" },
                  { "swflow", 's', 0, 0, 's',
                    "use software (XON/XOF) flow control" } ,
                  POPT_AUTOHELP
                  { NULL, 0, 0, NULL, 0 }
  };

  optCon = poptGetContext(NULL, argc, argv, optionsTable, 0);
  poptSetOtherOptionHelp(optCon, "[OPTIONS]* <port>");

  if (argc < 2) {
        poptPrintUsage(optCon, stderr, 0);
        exit(1);
  }

  /* Now do options processing, get portname */
  while ((c = poptGetNextOpt(optCon)) >= 0) {
     switch (c) {
        case 'c':
           buf[i++] = 'c';
           break;
        case 'h':
           buf[i++] = 'h';
           break;
        case 's':
           buf[i++] = 's';
           break;
        case 'n':
           buf[i++] = 'n';
           break;
     }
  }
  portname = poptGetArg (optCon);
  if((portname == NULL) || !(poptPeekArg (optCon) == NULL))
     usage (optCon, 1, "Specify a single port", ".e.g., /dev/cua0");

  if (c < -1) {
     /* an error occurred during option processing */
     fprintf(stderr, "%s: %s\n",
             poptBadOption (optCon, POPT_BADOPTION_NOALIAS),
             poptStrerror (c));
     return 1;
  }

  /* Print out options, portname chosen */
  printf ("Options  chosen: ");
  for (j = 0; j < i ; j++)
     printf ("-%c ", buf[j]);
  if (raw) printf("-r ");
  if (speed) printf("-b %d ", speed);
  printf ("\nPortname chosen: %s\n", portname);

  poptFreeContext (optCon);
  exit (0);
}