Manual entry for this command says: 'Note that the new cache does not take effect until the OS is rebooted.' It looks like it's not exactly a parallel thing. – skalee Apr 23 '19 at 14:36 3. However, It really took me a long time to find out how to work it out under MAC OS X. Somebody suggested me to turn to netinet/tcpvar.h, but still none of the aforementioned MACRO was found. So, my question is, How to implementation TCP KEEPALIVE under MAC OS X? P.S.: my MAC OS X version is 10.8.3,and my gcc/g version is 4.2.1.
Automatically back up all your files with Time Machine, which is built in to your Mac, or choose another backup method.
Create a backupYou can also use iCloud and iCloud Drive to store files, such as your photos, documents, and music.
Set up iCloud and iCloud DriveWhen you have a backup, you can use it to restore your files at any time, including after the original files are deleted from your Mac.
Restore from a backupMaking a backup is an important part of preparing your Mac for service, especially because some types of repair might require erasing or replacing your hard drive.
Get your Mac ready for serviceTo see the size of a specific file or folder, click it once and then press Command-I. To see storage information about your Mac, click the Apple menu in the top-left of your screen. Choose About This Mac and click the Storage tab. For Time Machine backups, it's good to use a drive that has at least twice the storage capacity of your Mac.
macOS can save space by storing your content in the cloud. This isn't a backup, but it includes new tools to make it easier to find and remove large or unwanted files before you make a backup.
Use Optimized Storage in macOSYou can use Disk Utility if you need to erase or format a storage device.
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