# File lib/gssapi/simple.rb, line 175
    def acquire_credentials(princ = @int_svc_name, opts = {:usage => :accept})
      min_stat = FFI::MemoryPointer.new :OM_uint32
      scred = FFI::MemoryPointer.new :pointer

      case opts[:usage]
      when :accept
        usage = LibGSSAPI::GSS_C_ACCEPT
      when :initiate
        usage = LibGSSAPI::GSS_C_INITIATE
      when :both
        usage = LibGSSAPI::GSS_C_BOTH
      else
        raise GssApiError, "Bad option passed to #{self.class.name}#acquire_credentials"
      end

      maj_stat = LibGSSAPI.gss_acquire_cred(min_stat, princ, 0, LibGSSAPI::GSS_C_NO_OID_SET, usage, scred, nil, nil)
      raise GssApiError.new(maj_stat, min_stat), "gss_acquire_cred did not return GSS_S_COMPLETE" if maj_stat != 0

      @scred = LibGSSAPI::GssCredIdT.new(scred.get_pointer(0))
      true
    end