### Method

# Gio TlsCertificate get_not_valid_before

since: 2.70

#### Declaration

    GDateTime*
    g_tls_certificate_get_not_valid_before (
      GTlsCertificate* cert
    )

#### Description

Returns the time at which the certificate became or will become valid.

Available since: 2.70

Gets property | `Gio.TlsCertificate:not-valid-before`

#### Return value

Type: `GDateTime`

The not-valid-before date, or `NULL` if it’s not available.

The caller of the method takes ownership of the data, and is responsible for freeing it.
The return value can be `NULL`.