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function is not described

get_post_timestamp() WP 5.3.0

Retrieve post published or modified time as a Unix timestamp.

Note that this function returns a true Unix timestamp, not summed with timezone offset like older WP functions.

No Hooks.

Return

Int/false. Unix timestamp on success, false on failure.

Usage

get_post_timestamp( $post, $field );
$post(int/WP_Post)
WP_Post object or ID.
Default: global $post object
$field(string)
Published or modified time to use from database. Accepts 'date' or 'modified'.
Default: 'date'

Changelog

Since 5.3.0 Introduced.

Code of get_post_timestamp() WP 5.5.1

<?php
function get_post_timestamp( $post = null, $field = 'date' ) {
	$datetime = get_post_datetime( $post, $field );

	if ( false === $datetime ) {
		return false;
	}

	return $datetime->getTimestamp();
}