• Created by Unknown User (mkos), last modified on Dec 10, 2014

This section outlines simple guidelines that you can follow to detect a real license, and if you don't find one, detect a trial license.

For example, say you have chosen a trial license as a way of providing your potential customer with demo versions of your software, but you might first want to check whether a real license is also available. (Note that there is no need to check or use a trial license if your end user has already bought a real one.) For this purpose, you can use the following code example to check out a license from a server, and when it is not available, to check out a trial license. If no licenses at all are available, the user will see the "Unable to checkout from trial license:" message, as shown below.

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

#include "lmx.h"

LMX_HANDLE LmxHandle;

void exit_on_error(LMX_STATUS s) 
{
  if (s != LMX_SUCCESS) 
  {
    if (LmxHandle != NULL) 
    {
      fprintf(stderr, "%s\n", LMX_GetErrorMessage(LmxHandle));
      LMX_Free(LmxHandle); // Release memory allocated by LM-X
    } 
    else 
    {
      fprintf(stderr, "%s\n", LMX_GetErrorMessageSimple(s));
    }
      fflush(stderr);
      exit(1);
    }
 }

int main()
{
  exit_on_error(LMX_Init(&LmxHandle));

  if (LMX_Checkout(LmxHandle, "f2", 1, 0, 1) != LMX_SUCCESS)
  {
    printf("Unable to checkout from server license:\n");
    printf("%s\n", LMX_GetErrorMessage(LmxHandle));

    // If we cannot checkout a license from the server, we set the trial option and try to checkout a trial license
    LMX_SetOption(LmxHandle, LMX_OPT_TRIAL_USES, (LMX_OPTION) 2);
    if (LMX_Checkout(LmxHandle, "f2", 1, 0, 1) != LMX_SUCCESS)
    {
      printf("Unable to checkout from trial license:\n");
      printf("%s\n", LMX_GetErrorMessage(LmxHandle));
      LMX_Free(LmxHandle);
      return 1;
    }
  }

  LMX_Free(LmxHandle);
  return 0;
}