Empty Trash / Deleting files. Are they really gone?

[Sylonien]

(New to iMac / Mac OS!)

Are all the files actually gone when you empty the trash can?
Are programs fully deleted when you simply drag them in to the trash can?

I've been using Windows all my life before so I'm use to stuff like uninstallers, registry, etc etc.

So I want to know whether it's all gone and not leave tons of rubbish behind buried somewhere in the system.

Thanks

 

[simsaladimbamba]

The files are gone in a way, that the OS has no access to them, thus special software is needed, to recover files emptied from the Trash.
The same goes for applications.
Best way to FULLY DELETE a program

Helpful Information for Any Mac User by GGJstudios​

To retrieve files, that have been deleted and also been emptied from the Trash, you can use
Data Rescue 3 (trial lets you scan the HDD and see, if data is recoverable, but to actually recover files, you need to buy the full version for 99 USD) or
FileSalvage (trial lets you scan the HDD and see, if data is recoverable, but to actually recover files, you need to buy the full version for 89.95 USD).

Also know, that you should immediately stop any writing processes to the actual HDD. If it is the same HDD as the one your operating system (OS) resides on, it is better to use an external HDD with Mac OS X on to boot from and install Data Rescue or FileSalvage onto to scan the HDD from which the data has been accidentally deleted.

 

[Fishrrman]

"Are all the files actually gone when you empty the trash can?"

That depends.

If you just use the regular "Empty Trash" command, it just deletes the directory entry for that file(s). The actual data that comprises the files remains on the drive's sectors until it is "written over" by NEW data. This may or may not happen right away.

If you use the "Secure Empty Trash" command, the OS deletes the directory entry for the file, AND, it "overwrites" the sectors on the drive where the data exists with a random pattern of "ones" and "zeros". After this is done, the data _is_ gone, and cannot be recovered by normal file-recovery techniques.

"Are programs fully deleted when you simply drag them in to the trash can?"

See explanation above.

In addition, even after you drag an application's icon to the trash, and delete it, there still may be some "fragments" of the program left elsewhere on your drive. For example, the app's "preferences" file may still be within your user account folder.

 

[GGJstudios]

Are programs fully deleted when you simply drag them in to the trash can?

I've been using Windows all my life before so I'm use to stuff like uninstallers, registry, etc etc.

On Mac OS X, there is no registry to worry about. When you drag an app to the Trash, it's fully uninstalled. However, there are files/folders left behind such as user preference lists, caches, etc. that don't affect your Mac, but take up disk space.

In most cases, app removal software doesn't do a thorough job of finding and removing files/folders related to deleted apps. For more information, read this.

The most effective method for complete app removal is manual deletion:

Best way to FULLY DELETE a program​

 

[old-wiz]

If you just use the regular "Empty Trash" command, it just deletes the directory entry for that file(s). The actual data that comprises the files remains on the drive's sectors until it is "written over" by NEW data. This may or may not happen right away.

Just wondering if it really deletes the directory entry or just marks it available? I used to work with file systems, but never went into the details of the OSx file system.

 

[Sylonien]

Thanks for the replies.

Like I said, not familiar with Mac file system. Just checking to see if there are tons of rubbish left behind taking up my SSD drive (space isn't exactly abundant at the moment.)

I haven't dived into the Library or system library to see if there are stuff left behind as I don't know my way around yet. I have removed some obvious stuff that they leave behind in Movies, Music, etc. folder sometimes.

But yeah, don't want to have it clogging up spaces or messing up the system with registry etc...

 

[mojobebop]

"Secure Empty Trash"

"Are all the files actually gone when you empty the trash can?"

That depends.

If you just use the regular "Empty Trash" command, it just deletes the directory entry for that file(s). The actual data that comprises the files remains on the drive's sectors until it is "written over" by NEW data. This may or may not happen right away.

If you use the "Secure Empty Trash" command, the OS deletes the directory entry for the file, AND, it "overwrites" the sectors on the drive where the data exists with a random pattern of "ones" and "zeros". After this is done, the data _is_ gone, and cannot be recovered by normal file-recovery techniques.

"Are programs fully deleted when you simply drag them in to the trash can?"

See explanation above.

In addition, even after you drag an application's icon to the trash, and delete it, there still may be some "fragments" of the program left elsewhere on your drive. For example, the app's "preferences" file may still be within your user account folder.

-----------------------
can you say what exactly is that command?

 

[mmomega]

The quick way to access Empty Trash.

Right click can to 'Empty Trash'
Cmd+Right Click to 'Secure Empty Trash'

You can also enable always secure empty trash from Finder->Prefs->Advanced