14 uses of REQUIREMENT_ERROR

color_requirements in drupal-6.x/modules/color/color.install
db_status_report in drupal-6.x/includes/database.pgsql.inc
Report database status.
db_status_report in drupal-6.x/includes/database.mysqli.inc
Report database status.
db_status_report in drupal-6.x/includes/database.mysql.inc
Report database status.
drupal_check_module in drupal-6.x/includes/install.inc
Check a module's requirements.
hook_requirements in documentation-6.x/developer/hooks/install.php
Check installation requirements and do status reporting.
install_check_requirements in drupal-6.x/install.php
Check installation requirements and report any errors.
system_requirements in drupal-6.x/modules/system/system.install
Implementation of hook_requirements().
system_status in drupal-6.x/modules/system/system.admin.inc
Menu callback: displays the site status report. Can also be used as a pure check.
theme_status_report in drupal-6.x/modules/system/system.admin.inc
Theme requirements status report.
unicode_requirements in drupal-6.x/includes/unicode.inc
Return Unicode library status and errors.
update_help in drupal-6.x/modules/update/update.module
Implementation of hook_help().
_update_cron_notify in drupal-6.x/modules/update/update.fetch.inc
Perform any notifications that should be done once cron fetches new data.
_update_requirement_check in drupal-6.x/modules/update/update.module
Private helper method to fill in the requirements array.