Visual Basic 6.0

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

See more OpenSSL Examples

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

Visual Basic 6.0

Dim success As Long
success = 0

Dim pkey As New PrivateKey

' Load the private key from an PEM file:
success = pkey.LoadPemFile("private.pem")
If (success = 0) Then
    Debug.Print pkey.LastErrorText
    Exit Sub
End If

Dim pubKey As New PublicKey
success = pkey.ToPublicKey(pubKey)

success = pubKey.SavePemFile(0,"pubKey.pem")
If (success <> 1) Then
    Debug.Print pubKey.LastErrorText

    Exit Sub
End If

Debug.Print "Success."