Either way, Mac OS X displays the Info dialog. Click the right-facing arrow next to the Sharing & Permissions heading to expand it. To change your own permissions on the item, click the Privilege pop-up menu next to your name — handily marked “(Me)” as well — and choose a new Ownership permissions level.
- App permissions are the privileges an app has—like being able to access your phone's camera or your laptop's contact list—but deciding which ones to switch on or off isn't an exact science.
- Mac OS X automatically sets permissions to limit a user’s access to system files and other user directories. If that protection isn’t good enough, you can change permissions to prevent other users from doing stuff like editing your 'Great American Novel,' reading private financial documents, or opening a specific application.
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␡- Managing Permissions via Command Line
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This chapter is from the book Change Mac App Permissions Settings
Apple Training Series: Mac OS X Support Essentials v10.6: A Guide to Supporting and Troubleshooting Mac OS X v10.6 Snow Leopard
This chapter is from the book
This chapter is from the book
Apple Training Series: Mac OS X Support Essentials v10.6: A Guide to Supporting and Troubleshooting Mac OS X v10.6 Snow Leopard
Managing Permissions via Command Line
Viewing and modifying file system permissions in the command line is both much richer and more complicated than in the Finder. The Finder has streamlined ownership, permissions, and ACLs, providing only the most common features that users require. However, the command line offers every conceivable ownership and permissions option. Further, the command line often provides more than one method for performing identical permissions tasks.
![Top mac app Top mac app](/uploads/1/3/3/9/133941251/617762456.png)
Viewing Traditional UNIX Permissions
Once again, the ls command is your primary tool for viewing file and folder information in the command line. The ls command has many options for viewing nearly any file or folder attribute. You can learn more about all the options available to ls from its manual entry page. Here, you will be presented with a few fundamental permissions viewing options.
The most basic ls option for viewing file and folder ownership and permissions is –l:
The first string of characters at the beginning of each line is shorthand for the item type and permissions. The following information appears from left to right: the number of hard links associated with the item (for most users, this particular bit will be trivial information), the assigned owner, the assigned group, the last modification date, and finally the item’s name.
The syntax for the abbreviated information section is:
- The first character is item type: - for file, d for folder, and l for symbolic link.
- The next three characters indicate the owner’s permissions: - for no access, r for read access, w for write access, and x for file execute access or folder browsing access.
- The middle set of three rwx or - characters indicate the group’s permissions.
- The final set of three rwx or - characters indicate everyone else’s permissions.
- Optionally, there may be a + at the end to indicate that the item has ACL rules applied to it, or an @ at the end to indicate that the item has extended attributes.
Change Permissions Mac Terminal
The execute privilege attribute x has not been introduced yet, but it is the third standard UNIX privilege attribute after read and write. The execute privilege is enabled on files that are commands and applications (or folders that contain application bundles), to indicate that the item contains executable software code. The execute privilege is also required on normal folders to access the contents of the folder. The Finder doesn’t show you when the execute privilege is used, but it will properly manage the execute privilege when you make permissions changes using the Get Info window.
Viewing Access Control Lists (ACLs)
The ACL technology is more advanced than traditional UNIX-style permissions because it allows for an arbitrary number of user and group permissions rules per item. Each permissions rule is known as an Access Control Entry (ACE). Every file and folder on the system can have an unlimited list of ACE rules, hence the “list” in ACLs.
From the command line, Mac OS X’s ACL implementation provides more than a dozen unique privilege attribute types and lets you define each as a specific allow or deny rule. In other words, you can assign an item an unlimited number of user or group rules, or ACEs, which can be used to allow or deny any of the following privilege attributes:
- Administration—Administration attributes, which define a user’s or group’s ability to make permissions changes, include change privileges and change ownership.
- Read—Read attributes define a user or group’s ability to read items and include read attributes, read extended attributes, read file data or list folder contents, execute file or traverse folder, and read permissions.
- Write—Write attributes define a user’s or group’s ability to make changes and include write attributes, write extended attributes, read file data or create files in folder, append file data or create new subfolder inside folder, delete item, and delete subfolders and files.
Furthermore, each ACE for a folder can include a static inheritance rule that defines whether the folder’s permissions also apply to new items placed in the folder. Inheritance attributes include the following: no inheritance, apply to just new items in this folder, apply to any new child folders, apply to any new child files, and apply to all descendants of this folder.
To view an item’s ACLs alongside their permissions, simply add the -e option to the -l option:
Modifying File Permissions via Command Line
You will use two primary commands for changing file and folder permissions in the command line: chown for changing ownership and chmod for changing privileges.
Changing Ownership via Command Line
Short for “change ownership,” chown will let you change the owner and group associated with a file or folder. Using chown often requires root access, so this command is almost always preceded by the sudo command. To use chown, enter the new owner’s name, followed optionally by a colon and the new group name, and then finish with the item’s path. In the following example, Michelle will use the chown command to change testfile1’s ownership to the user account “kevin” and the group account “admin.”
Changing Privileges via Command Line
Short for “change file mode,” chmod will let you change the privileges associated with a file or folder. Using chmod on files you don’t own requires root access, so the chmod command is often preceded by the sudo command. To use chmod, enter the new privileges first followed by the item’s path.
As for changing privileges, there are two basic methods when using the chmod command:
- Using alphanumeric abbreviations—The basic syntax goes: account type, modifier, and then privilege. Account types include u for owner, g for group, and o for everyone else. Modifiers include + for allow, - for deny, and = for exact setting. Privileges are as expected with r for read, w for write, and x for execute or folder access. For example, if you’re using this method to allow full access for the owner and group but read-only access for everyone else, you’d enter ug=rwx,o=r.
- Using octal notation—As you can see, chmod extensively uses shortcuts and abbreviations. To save even more keystrokes you can use octal notation, which uses numeric abbreviations for defining privileges. Best poker app for beginners mac. The basic syntax for octal notation is to use a single-digit number for the user first, followed by a single number for the group, and then a last single number for everyone else. Octal notation uses 0, for no access; 1, for execution only; 2, for write-only; and 4, for read-only. To use mixed permissions, simply add the numbers together. For example, if you’re using this method to allow for full access to a folder for the owner and group but read-only access for everyone else, you’d type 775.
In the following example, Michelle will use the chmod command to change the permissions of testfile1 and testfolder to allow read and write access for the owner and the group but read-only access for everyone else. She will first use alphanumeric abbreviations, and then octal privilege equivalents.
Using the Sticky Bit
As mentioned previously in this chapter, the /Users/Shared folder has a unique permission setting that allows all local users to read and write items into the folder yet prevents other users from being able to delete files that they didn’t originally put in this folder. This special permissions configuration is brought to you courtesy of the “sticky bit.” Essentially, enabling the sticky bit on a folder defines it as an append-only destination, or, more accurately, a folder in which only the owner of the item can delete the item.
You can clearly see the sticky bit setting of the /Users/Shared folder when you view its ownership and permissions. Note the t on the end of the permissions information, which indicates that the sticky bit is enabled:
You can enable sticky bit functionality similar to the /Users/Shared folder on any other folder using a special octal notation with the chmod command. In the following example, Michelle has already created a new folder named NewShared. She then uses the chmod command with +t to set sharing for all users with sticky bit functionality:
Managing Locked Items via Command Line
As mentioned previously, Mac OS X includes a special file system lock feature that prevents anyone but the owner of an item from making changes to that item. Any user can easily lock a file or folder he owns from the Finder’s Get Info window, also covered earlier in this chapter.
The problem with the file system lock is that the Finder prevents even other administrative users from making changes or even unlocking items they don’t own. In fact, this file system lock extends to the command line as well. Even with sudo access, an administrator is not allowed to change a locked item—with one important exception, the chflags command. This command allows the administrator to change file system flags, which among other things allows you to lock or unlock any file or folder on the system.
In the following example, Michelle needs to change the permissions of a folder owned by another user so the folder can be shared. However, even using sudo she is denied access from doing this, indicating the file is locked. She verifies this by using ls –lO to view the file listing with file flags, which indeed returns that the folder is locked, “uchg”. She then uses the chflags command with the nouchg option to unlock the folder. Finally, she is able to make changes to the previously locked file.
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Our phones contain so much of our personal data and it’s imperative we protect our privacy with all the necessary tools. These may be in any form like security patches, anti-virus updates, app lockers, etc. In midst of all these, a gullible aspect escapes our attention — Android app permissions.
When it comes to the world of apps, as you might already know, it’s not as rosy as it appears. Some of the apps do their designated work brilliantly, while a few others do a ‘tad‘ more than that.
In this era where we often question our privacy and the reach of digitization, it’s only natural that we understand how Android app permissions work and what does it mean to provide them with the data that they request.
![Top mac app Top mac app](/uploads/1/3/3/9/133941251/692839721.jpg)
App Permissions: An Overview
In simple words, permissions are special rights that an app must have, in order to function properly. It can either be a permission for the hardware aspect of your phone or it can be one pertaining to the software side — reading/modifying information.
Depending on the sensitivity of the area, the system can either grant the permission automatically or it’ll ask the user.
For instance, a simple messaging service would need permission to use contacts while a hybrid version messaging service (read WhatsApp) will require much more than the plain simple Contacts permission.
Prior to Android Marshmallow, users weren’t given the freedom to choose the permission level. Thankfully, post the introduction of Android Marshmallow, users can now freely decide which all set of permissions should an app have access too.The permission levels can be easily checked from within the Settings menu or from the app page in Google Play. And should you find an app seeking permission beyond its functionality, then you know that something’s up.
But before that — which permission an app should or shouldn’t have — it’s important that we understand how app permissions work.
Also See: 5 Most Popular Android Apps, Games and More on Google PlayHow do App Permissions Work?
By default, a basic Android app doesn’t have any permissions which mean that it can’t go about its job without impacting the user’s experience. Google provides about 17 permissions in total for apps to work. These permissions must be defined by the app before it can have access.
On the user’s front, they must agree to before the app can start using the data or the hardware.
These permissions are handled by the Android API framework which calls for the validation process to verify if an app has the necessary permission to function. And if not, you’ll get a pop-up each time, the app tries to access the permission and finds it blocked.
There was a time when Android developers had to record even the tiniest of app permissions like the vibration of the mobile phone.
However, much has changed and now developers have to list whether the app that they are building needs to have normal permissions or dangerous permissions in the manifests.Normal permissions are the ones that don’t pose a risk to the user’s data or privacy, while dangerous permissions are the ones which can potentially affect the user’s data or functionality of the device. It’s these permissions that we can either accept or deny.
Why Should You Care?
It’s all about data privacy. For instance, a clock app or a calculator app shouldn’t ask permission for location access or the contacts. Just this year, in January, revelations were made about the beauty app Meitu which sought permissions way above its limits — GPS location, cell carrier information, Wi-Fi connection data, SIM card information, jailbreak status — which made the common user question the developer’s true motives.
There have also been instances where apps ask permissions to access Contacts lists and when given by an unwary user, would upload the same on its servers.
This again leads us to the believe that the popular apps wouldn’t resort to asking permissions for which it has no business. But then, don’t get mislead.
Even popular apps like the Facebook Messenger or Moments requests a slew of permissions. Thankfully, the ball is in our court to decide whether we would like to give the same or not.Common App Permissions
How to use mac app shortcuts to open app store. Aforesaid, there are roughly 17 permissions that are there on Android. While some lesser known may be grouped under similar headings, here are some of the most common ones.
1. Contacts
The ability of an app to access the device’s contacts. When enabled, the app also has the ability to read as well as to modify them.
2. Location
If you are a regular Google Maps user, you must be knowing what this permission does. It helps the device to get a location approximation through the GPS of your Android.
There are two sets of location permissions, though — precise and approximate.
3. In-app Purchases
The permission set through which one can purchase content inside the app. For instance, upgrading to the pro version
4. Phone
The Phone permission accomplishes a diverse set of functionalities like call, read and modify the call log. How to make folders into apps mac. However, the shady apps can also make calls without the user’s knowledge which can cost money.
5. Storage
A majority of the apps have this permission set, particularly the camera apps and the browser apps, among others. In a more broader sense, this means the ability to read and write data from the storage — both internal and external.
Did you Re-Visit the App Permissions?
In today’s world where seldom anything remains private, thanks to the insane security attacks, it’s imperative that you revisit all the app permissions one by one. You can either scrutinize them app wise or permission wise — the choice is yours. However, do make sure that it is done straight away. After all, you wouldn’t want some stranger stealing data right from under your nose.
Also Read: How to Securely Wipe Your Android Phone Before Selling It
The above article may contain affiliate links which help support Guiding Tech. However, it does not affect our editorial integrity. The content remains unbiased and authentic.Also See#gtexplains #security
Did You Know
Rootkits are a type of Trojan horse and are designed to conceal certain objects in your system.