4 calls to _batch_page()

authorize.php in ./authorize.php
Administrative script for running authorized file operations.
install_run_task in includes/install.core.inc
Runs an individual installation task.
system_batch_page in modules/system/system.admin.inc
Default page callback for batches.
update.php in ./update.php
Administrative page for handling updates from one Drupal version to another.

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