In the Mail app on your Mac, choose Mail Preferences, then click Rules. To review an example of a rule, select a provided rule, then click Edit. To close the rule, click Cancel. Click Add Rule, then type a name for the rule. Indicate whether any or all of the conditions must be true for the rule to be applied to a message. Specify the conditions. Nov 19, 2019 MAC address filtering adds an extra layer to this process. Before letting any device join the network, the router checks the device's MAC address against a list of approved addresses.

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When you add your email accounts (such as iCloud, Exchange, school, or work) to Mail, you get all your emails in one place—without signing in to any websites.

Reduce the noise

Keep your inbox and attention focused by blocking emails from specific people or groups.

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You don’t need to keep everything in your inbox—mailboxes are an easy way to organize your emails.

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It’s easy to find an email message, no matter which mailbox or folder it’s hiding in.

To browse the Mail User Guide, click Table of Contents at the top of the page.

If you need more help, visit the Mail Support website.

A file system handles the persistent storage of data files, apps, and the files associated with the operating system itself. Therefore, the file system is one of the fundamental resources used by all processes.

APFS is the default file system in macOS, iOS, watchOS, and tvOS. APFS replaces HFS+ as the default file system for iOS 10.3 and later, and macOS High Sierra and later. macOS additionally supports a variety of other formats, as described in Supported File Systems.

Regardless of the underlying format, all of the disks attached to the device—whether they are physically plugged in or are connected indirectly through the network—contribute space to create a single collection of files. Because the number of files can easily be many millions, the file system uses directories to create a hierarchical organization. Although the basic directory structures are similar for iOS and macOS, there are differences in the way each system organizes apps and user data.

Before you begin writing code that interacts with the file system, you should first understand a little about the organization of file system and the rules that apply to your code. Aside from the basic tenet that you cannot write files to directories for which you do not have appropriate security privileges, apps are also expected to be good citizens and put files in appropriate places. Precisely where you put files depends on the platform, but the overarching goal is to make sure that the user’s files remain easily discoverable and that the files your code uses internally are kept out of the user’s way.

About the iOS File System

The iOS file system is geared toward apps running on their own. To keep the system simple, users of iOS devices do not have direct access to the file system and apps are expected to follow this convention.

iOS Standard Directories: Where Files Reside

For security purposes, an iOS app’s interactions with the file system are limited to the directories inside the app’s sandbox directory. During installation of a new app, the installer creates a number of container directories for the app inside the sandbox directory. Each container directory has a specific role. The bundle container directory holds the app’s bundle, whereas the data container directory holds data for both the app and the user. The data container directory is further divided into a number of subdirectories that the app can use to sort and organize its data. The app may also request access to additional container directories—for example, the iCloud container—at runtime.

These container directories constitute the app’s primary view of the file system. Figure 1-1 shows a representation of the sandbox directory for an app.

An app is generally prohibited from accessing or creating files outside its container directories. One exception to this rule is when an app uses public system interfaces to access things such as the user’s contacts or music. In those cases, the system frameworks use helper apps to handle any file-related operations needed to read from or modify the appropriate data stores.

Table 1-1 lists some of the more important subdirectories inside the sandbox directory and describes their intended usage. This table also describes any additional access restrictions for each subdirectory and points out whether the directory’s contents are backed up by iTunes and iCloud.

**Table 1-1** Commonly used directories of an iOS app
Directory	Description
Download cnn app for mac. AppName`.app` Business expense software for mac. Activity & Expense Tracker is a time management and billing program that will allow you to track all of your business activities and expenses in one, easy-to-use cross-platform database. Zoho Expense offers a free small business expense tracking software plan for 3 users that lets you auto-scan 100 receipts per month, track projects, import card transactions, convert currency, and store up to 5 GB of receipt documents. Zoho Expense’s Premium and Enterprises are not free but can accommodate more users, allows for an unlimited.	This is the app’s bundle. This directory contains the app and all of its resources. You cannot write to this directory. To prevent tampering, the bundle directory is signed at installation time. Writing to this directory changes the signature and prevents your app from launching. You can, however, gain read-only access to any resources stored in the apps bundle. For more information, see the Resource Programming Guide The contents of this directory are not backed up by iTunes or iCloud. However, iTunes does perform an initial sync of any apps purchased from the App Store.
`Documents/`	Use this directory to store user-generated content. The contents of this directory can be made available to the user through file sharing; therefore, this directory should only contain files that you may wish to expose to the user. The contents of this directory are backed up by iTunes and iCloud.
`Documents/Inbox`	Use this directory to access files that your app was asked to open by outside entities. Specifically, the Mail program places email attachments associated with your app in this directory. Document interaction controllers may also place files in it. Your app can read and delete files in this directory but cannot create new files or write to existing files. If the user tries to edit a file in this directory, your app must silently move it out of the directory before making any changes. The contents of this directory are backed up by iTunes and iCloud.
`Library/`	This is the top-level directory for any files that are not user data files. You typically put files in one of several standard subdirectories. iOS apps commonly use the `Application Support` and `Caches` subdirectories; however, you can create custom subdirectories. Use the `Library` subdirectories for any files you don’t want exposed to the user. Your app should not use these directories for user data files. The contents of the `Library` directory (with the exception of the `Caches` subdirectory) are backed up by iTunes and iCloud. For additional information about the Library directory and its commonly used subdirectories, see The Library Directory Stores App-Specific Files.
`tmp/`	Use this directory to write temporary files that do not need to persist between launches of your app. Your app should remove files from this directory when they are no longer needed; however, the system may purge this directory when your app is not running. The contents of this directory are not backed up by iTunes or iCloud.

An iOS app may create additional directories in the Documents, Library, and tmp directories. You might do this to better organize the files in those locations.

For information about how to get references to the preceding directories from your iOS app,

Make Mac Mail App Use Specific Network Interface