drupal_tempnam in core/includes/drupal.inc

Creates a file with a unique filename in the specified directory.

file_example_unmanaged_php_submit in modules/examples/file_example/file_example.module

Submit handler to write an unmanaged file using plain PHP functions.

file_unmanaged_save_data in core/includes/file.inc

Saves a file to the specified destination without invoking file API.

image_gd_save in core/modules/system/image.gd.inc

GD helper to write an image resource to a destination file.

installer_manager_local_transfers_allowed in core/modules/installer/installer.manager.inc

Determines if file transfers will be performed locally.

LocaleExportFunctionalTest::testExportTranslation in core/modules/locale/tests/locale.test

Test exportation of translations.

LocaleImportFunctionalTest::importPoFile in core/modules/locale/tests/locale.test

Helper function: import a standalone .po file in a given language.

LocalePluralFormatTest::importPoFile in core/modules/locale/tests/locale.test

Imports a standalone .po file in a given language.