V600-Filters

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Contents 1 Filters 1.1 Creating Filters 1.2 Associating Filters with Groups 2 Example Procedure for Adding a Filter

Filters

Many newsgroups contain very large numbers of posts. The NewsBin Filter system is used to help you find posts in such newsgroups.

Dynamic and Display filters are those that are applied at the top of Post lists after you have done a Show Posts or Show All Posts to load up headers in a Post list. You will find yourself using this type of filter all the time.

The different type of filter conditions are handled in an additive mode. This means that if you set multiple conditions then only those posts that match all the specified conditions are displayed.

The Display filters available are:

• Search
  This allows you to filter post according to keywords in the Subject line. In the simplest case you simply type in the keywords of interest press Enter (or click find). For those who want to type more complex find expressions NewsBin will actually accept expressions that conform to standard Regular Expression syntax. A Regular Expression cheat sheet can be found here.
• Show filenames
  This is a simple toggle between NewsBin displaying the full subject line or trying to isolate the filename part from the subject line and displaying just that information. Note that when trying to display the filenames NewsBin has to make some guesses as to which part of the subject is the filename, and this tends to only be reliable with yEnc encoded posts where a standard is stipulated as to how the filename should be represented in Subject lines. Note also that it is always possible that when a file is actually downloaded it turns out to have a different name encoded in the file to that suggested by the subject, although this is relatively rare.
• Compact View
  NewsBin has always consolidated all the posts that make up a single file into one line in a Post list. The Compact view option attempts to take this a stage further by consolidating all the files that make up a file set into a single line in the Post list. How successfully NewsBin is in doing this depends on how consistently the Subject lines for the fileset are structured.
• Hide Old
  This is the key setting to use if you are primarily interested in seeing only those posts that are new. To take advantage you need to adopt a policy of clearing the "new" status when you have processed a post. This can be done manually using the Mark Post Old or Mark All Old options, or you can tell NewsBin to automatically mark all posts in a Post list as Old when you close it by setting the Auto-Mark Old option under Options->Switches.
• Load
  Defaults to Display Age and allow you to select different age ranges of posts to load from your stored headers into the Post List display. A new selection will reload the display rather than filter the existing display.

The Dynamic filters available are:

• Filter profile
  This option allows you to pick up a previously prepared set of filter criteria that have been prepared as described below.
• Age
  This allows you to limit the posts displayed to the specified age. Note that this setting does not stop those posts being loaded in the first place - that can be controlled using the Display Age setting at either the global or group level.
• Xpost
  The cross post filter allows you to limit posts that have been posted to the specified number of groups (or less). A typical use of this setting is to try and remove Spam post as they tend to be cross-posted to lots of groups.
• Max Size
  This allows you to put an upper limit on the size of the post you are interested in seeing. This option is not that often used if you have a high-speed internet connection, but could well be relevant if your connection is low speed so you cannot afford to try and download really large items.
• Min Size
  This allows you to set the minimum size post that you are interested in seeing. This would normally be used to filter out text posts as they tend to be much smaller than binary posts. When using this option it would be quite normal to have set the Show PAR/NFO option under Options->Switches to allow these types of file through regardless of their size.

Stored filters are ones that have been previously prepared and saved. Uses of such filters might be:

• Restricting the amount of material that you see in a group.
• Acting as a Watch Filter to help you find items that you are hoping will arrive in the future. Note that when used in this mode NewsBin will not discriminate between multiple postings of the same type if they all match the filter criteria.
• Searching the stored headers to see if anything matching the filter can be found. This is a form of the Watch Filter type of use mentioned above.
• Used in conjunction with the 'Automatic Download option for downloading files without manual intervention.

Creating Filters

You can create new filters or edit existing filters. It is good practice not to edit the default "Global Filter" to any significant amount. The 'global' filter with standard settings can be used in effect as "no filters applied". As the global filter is by default applied to every group you will find it much easier to create custom filters for special cases.

To create anew filter use the "New" button. This will then ask you which filter should be used as a model, and the name of the new filter. Once a filter has been created then highlighting it from the list at the left will display its details and allow them to be edited. If you want to delete a filter then highlight it in the list at the left and press the DEL key.

• Minimum/Maximum File Size
  This has exactly the same meaning as in the dynamic filters described above.

• Crosspost Filter
  This has exactly the same meaning as in the dynamic filters described above.

• Age Filter
  This has exactly the same meaning as in the dynamic filters described above.

• Subject/Filename Filters
  You will see that there are tabs for two different types of filters. The Subject filters applies to headers that are downloaded and can be used to filter according to the text in the Subject field of headers. This means that it can be applied before any files are downloaded to help you identify which files should be added to the download list. The filename filters on the other-hand apply at the download stage. They are applied to the name of the file that is to be downloaded (which may be completely different to the subject field) so to apply the Filename filters NewsBin needs to download at least the first chunk in the file.

• Accept/Reject Filters
  There are two types of action you can take in Subject and Reject filters. If you set the Accept options then you are saying that you only want files that match one of the accept criteria. If you set the Reject options then you are saying that you do not want any files that match this criteria. If there is any conflict between Accept and Reject settings then the Reject setting over-rides the Accept setting.
  To add a new entry to one of these filters type the text for the filter into the input box and then press the Add button. To remove an entry highlight it and press the DEL key. You cannot edit an entry - instead you have to remove the entry and then re-add it in its corrected form.
  The strings that are entered into the text fields for the Accept and Reject filters use Regular Expression syntax. For those who do not want to worry about the Regular Expression syntax then just type the keywords you are interested in finding into the input box. If you enter multiple criteria on different lines then there is an implicit OR between them so that matching any of the criteria will result in a match. The CaSe Of tHe TexT in a Regular Expression does not matter.
  • Common examples

Text highlighted where match failure occurs and highlighted where an unexpected match may occur.

Regular Expression	Match Examples	Non-Matching Examples
example\.one\.exact\.match	example.one.exact.match	example.one.exact.match.extra.text extra.text.example.one.exact.match
.*example two\.any characters.*	any characters before example two.any characters after also beforexample two.any charactersubsequently after eXaMpLe TWO.ANY ChArAcTeRs	something before example two.any extra characters something after
slash\\bracket\[parenthesis\(	slash\bracket[parenthesis(	slash\bracketextra[parenthesis(

You can test a filter that you have prepared by using "Show All Posts" on a group that you want to use with the filter; making sure that Enable Filters is ticked at the top of the post list, and then selecting the filter of interest from the Filter Profile drop down.

Associating Filters with Groups

The first thing you have to decide is whether you want a filter to be associated permanently with a group or not.

If you do not want the filter to be permanently associated with a group, then you can simply select it from the drop down list at the top of a Post list. This filter will then be applied to the headers that are currently loaded into that Post list. As soon as you close the Post list NewsBin will revert to using whatever profile is set as the groups Filter Profile.

If you want a filter to be permanently associated with a group then carry out the following steps:

1. Right Click the group of interest and select Properties.
2. Make sure the Use Profile checkbox is ticked
3. Select the profile you want to use from the drop-down list.

Example Procedure for Adding a Filter

This example illustrates how to create a Multimedia filter profile that will only show multimedia files in a post list.

1. Click the Add Filters button from the toolbar
2. Click "New..." on the Filter Profiles screen
3. Enter a filter profile name like "Multimedia".
4. Click Ok
5. Select "Multimedia" in the Filter Profile column so it is highlighted
6. Click the Enable Filter checkbox
7. Enter \.mpg in the box to the right of the "Add" button then click "Add"
8. You should see it show up in the Filter Accept box of the Subject Accept tab.
9. Repeat step 7 for the other filename extensions like \.avi, \.wmv, \.mov
10. Hit Ok
11. When you load a group, to apply this filter, click "Enable Filters" and then select "Multimedia" from the "Filters" drop-box

In step 7, these are in the format of Regular Expressions. The slash is an escape to make sure you get the "." for the extension. To pick up both mpg and mpeg files, use "\.mpe?g". This will allow 0 or 1 "e"'s.