(C) Generate TOTP using Base32 Secret (6 Digits, Time-based, 30-second period)

Generates a 6-digit time-based TOTP code using a base32 secret with a 30-second time period.

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#include <C_CkCrypt2.h>
#include <C_CkStringBuilder.h>

void ChilkatSample(void)
    {
    HCkCrypt2 crypt;
    const char *secretKey;
    HCkStringBuilder sbKey;
    BOOL success;
    int numRemoved;
    int numDigits;
    int timePeriod;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.
    // 
    crypt = CkCrypt2_Create();

    // Base32 secret key:
    secretKey = "oebf ytfl qmzb p4xd 2ztf zyz4 hjrw 3uyo";

    sbKey = CkStringBuilder_Create();
    success = CkStringBuilder_Append(sbKey,secretKey);

    // Remove SPACE chars.
    numRemoved = CkStringBuilder_Replace(sbKey," ","");

    // Note: A new token is generated every 30 seconds.  You must generate within the same 30 second interval to get the same result.

    // Generate 6 digits.
    numDigits = 6;
    // 30 second time period.
    timePeriod = 30;
    printf("Your token is: %s\n",CkCrypt2_totp(crypt,CkStringBuilder_getAsString(sbKey),"base32","0","",timePeriod,numDigits,-1,"sha1"));


    CkCrypt2_Dispose(crypt);
    CkStringBuilder_Dispose(sbKey);

    }