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C

Export a Private Key as Traditional PEM

See more Private Key Examples

Demonstrates the Chilkat PrivateKey.GetPkcs1Pem method, which exports the key as unencrypted PEM, preferring the traditional algorithm-specific representation when one exists (for example -----BEGIN RSA PRIVATE KEY-----). It takes no arguments.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: Before PKCS #8 unified key storage, each algorithm had its own PEM format — RSA PRIVATE KEY, EC PRIVATE KEY, and so on. Some older tools still expect that traditional form, and this method produces it. When you have the choice, PKCS #8 (GetPkcs8Pem) is the more interoperable modern option; use this for compatibility with software that requires the legacy layout.

Chilkat C Downloads

C
#include <C_CkPrivateKey.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkPrivateKey privKey;
    const char *pem;

    success = FALSE;

    //  Load a private key to export.
    privKey = CkPrivateKey_Create();
    success = CkPrivateKey_LoadPemFile(privKey,"qa_data/private.pem");
    if (success == FALSE) {
        printf("%s\n",CkPrivateKey_lastErrorText(privKey));
        CkPrivateKey_Dispose(privKey);
        return;
    }

    //  Export as unencrypted PEM, preferring the traditional algorithm-specific representation when
    //  one exists (for example "-----BEGIN RSA PRIVATE KEY-----").
    pem = CkPrivateKey_getPkcs1Pem(privKey);
    if (CkPrivateKey_getLastMethodSuccess(privKey) == FALSE) {
        printf("%s\n",CkPrivateKey_lastErrorText(privKey));
        CkPrivateKey_Dispose(privKey);
        return;
    }

    printf("%s\n",pem);


    CkPrivateKey_Dispose(privKey);

    }