hook_widget_settings_alter() is missing in D7 (and D8) and several D6 modules cannot be ported to D7 because of this.

Closest existing thing currently is hook_field_attach_form(), that is called at the end of field_attach_form() and lets you alter the form parts generated by Field API - includes all the fields in the object.

Not sure you will be happy, but you can add a #process to all textfields by altering element_info (or textarea, select, button, ...). Then you get a chance to make changes .

The current situation is not "anti-form api". can you intercept every time any other modules attaches its stuff to any form?

Moshe, that's totally not a solution, a widget can contain many elements -- and while I do not expect to be able to alter any one-off, unstructured form like that but widgets are different.

Subscribing.

This used to be possible with D6 CCK by implementing hook_widget_settings_alter()
Any news about this issue?

Marking this as a duplicate of #982764: Document how to upgrade CCK field modules that used hook_widget_settings_alter

Well I guess it is time to reopen this issue as #982764: Document how to upgrade CCK field modules that used hook_widget_settings_alter has been moved to the documentation project and gets absolutely no real progress there.

Somebody will tell us again that this is not a bug. But:
- Things that were possible in D6 are no longer possible in D7: Isn't this a major bug?
- Several modules are dying because of this, e.g.
http://drupal.org/project/imagefield_focus
http://drupal.org/project/ad_gallery
http://drupal.org/project/node_repeat
- This is not a documentation bug as nobody has been able to a provide any viable solution to this so far (See #982764: Document how to upgrade CCK field modules that used hook_widget_settings_alter)
- If it was only a documentation issue, then hook_widget_settings_alter() would not have been added to CCK (See #417122: Allow drupal_alter() on Field and Widget Settings)

animelion

I did let #982764: Document how to upgrade CCK field modules that used hook_widget_settings_alter drop out of my radar.

Current way :
- use hook_field_widget_info_alter() to expose your additional settings
- use hook_form_field_ui_field_edit_form_alter() to add the form elements to edit the settings in the Field UI screen. If placed properly, the submitted values get saved automatically in the $instance['widget']['settings'] definition.
- use hook_field_attach_form() to alter the actual widgets in entity edit forms. You have to navigate through the $form to the location of the widgets you want to affect (in $form[$field_name][$langcode], the rest depends on the shape of the widget you want to alter), but the D6 versions probably had to do something similar. That part will get easier if/when #1204230: Missing hook_field_widget_form_alter() lands.

sub

This is definitely a doc issue. Let's fix it in the other issue.

FYI, this issue has been fixed in code: it was definitely not a documentation issue!
#1204230: Missing hook_field_widget_form_alter()