GetChecksum
virtual status_t GetChecksum(BString& checksum) const = 0;
virtual status_t GetChecksum(BString& checksum) const;
virtual status_t GetChecksum(BString& checksum) const;
virtual status_t GetChecksum(BString& _checksum) const;
ChecksumFileChecksumAccessor::GetChecksum(BString& checksum) const
status_t result = fExpectedChecksumAccessor->GetChecksum(expectedChecksum);
result = fRealChecksumAccessor->GetChecksum(realChecksum);
if ((result = checksumAccessor.GetChecksum(checksum)) != B_OK) {