constant BACKDROP_MINIMUM_PHP

bootstrap.inc in core/includes/bootstrap.inc

Functions that need to be loaded on every Backdrop request.

drupal.inc in core/includes/drupal.inc

Contains constants and function wrappers for Drupal 7.x compatibility.

hook_requirements in core/modules/system/system.api.php

Check installation requirements and do status reporting.

install_profile_info in core/includes/install.inc

Retrieves information about an installation profile from its .info file.

system_requirements in core/modules/system/system.install

Implements hook_requirements().

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