(C) Duplicate openssl pkey -in private.pem -pubout -out pubkey.pem

How to output the public part of a private key: Demonstrates how to duplicate this OpenSSL command:

openssl pkey -in private.pem -pubout -out pubkey.pem

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#include <C_CkPrivateKey.h>
#include <C_CkPublicKey.h>

void ChilkatSample(void)
    {
    HCkPrivateKey pkey;
    BOOL success;
    HCkPublicKey pubKey;

    pkey = CkPrivateKey_Create();

    // Load the private key from an PEM file:
    success = CkPrivateKey_LoadPemFile(pkey,"private.pem");
    if (success != TRUE) {
        printf("%s\n",CkPrivateKey_lastErrorText(pkey));
        CkPrivateKey_Dispose(pkey);
        return;
    }

    pubKey = CkPrivateKey_GetPublicKey(pkey);
    if (CkPrivateKey_getLastMethodSuccess(pkey) == FALSE) {
        printf("%s\n",CkPrivateKey_lastErrorText(pkey));
        CkPrivateKey_Dispose(pkey);
        return;
    }

    success = CkPublicKey_SavePemFile(pubKey,FALSE,"pubKey.pem");
    if (success != TRUE) {
        printf("%s\n",CkPublicKey_lastErrorText(pubKey));
        CkPublicKey_Dispose(pubKey);
        CkPrivateKey_Dispose(pkey);
        return;
    }

    printf("Success.\n");

    CkPublicKey_Dispose(pubKey);


    CkPrivateKey_Dispose(pkey);

    }