Start up from macOS Recovery
Perfect badger mac os. Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps: Mice escape mac os.
I can't spend $3,000 with Apple to get a MacBook with 16GB to give up 250GB of hard drive space for the same size screen just to run the newer OS and update Firefox. It is unreasonable for Firefox support to have been dropped for MAC OS systems prior to 10.9 - it's a. Shut down your Mac, turn it on while holding down Command+R. Your Mac will boot into the recovery partition. If you're using an older Mac (from 2010 or earlier), there's a chance that you can't use Recovery Mode. On those devices, hold 'Option' while turning your computer on, then select the recovery partition instead.
Apple silicon
Turn on your Mac and continue to press and hold the power button until you see the startup options window. Click the gear icon labeled Options, then click Continue.
Mac users may occasionally find themselves wanting to clean install macOS Big Sur onto a Mac. A clean installation of macOS Big Sur basically means the entire hard drive – including the system itself, all data, all apps, user accounts, literally everything – is erased, and then a fresh clean install of macOS Big Sur is installed onto the Mac. Apr 27, 2021 Turn on your Mac and continue to hold the power button until you see the startup options window, which shows your bootable volumes and a gear icon labled Options. Select the volume containing the bootable installer, then click Continue. When the macOS installer opens, follow the onscreen instructions. Hi folks, I did not find a similar topic if it was already created. I moved from my old mac pro to a new one. I installed the Epic Games Launcher from scratch and the problem is that hangs with preparing. I tried to clean up the installation but it did not help. The last lines in the logs: 2020.03.22-23.51.40:868396Port.
Intel processor
Make sure that your Mac has a connection to the internet. Then turn on your Mac and immediately press and hold Command (⌘)-R until you see an Apple logo or other image.
If you're asked to select a user you know the password for, select the user, click Next, then enter their administrator password.
Reinstall macOS
Select Reinstall macOS from the utilities window in macOS Recovery, then click Continue and follow the onscreen instructions.
Follow these guidelines during installation:
- If the installer asks to unlock your disk, enter the password you use to log in to your Mac.
- If the installer doesn't see your disk, or it says that it can't install on your computer or volume, you might need to erase your disk first.
- If the installer offers you the choice between installing on Macintosh HD or Macintosh HD - Data, choose Macintosh HD.
- Allow installation to complete without putting your Mac to sleep or closing its lid. Your Mac might restart and show a progress bar several times, and the screen might be empty for minutes at a time.
After installation is complete, your Mac might restart to a setup assistant. If you're selling, trading in, or giving away your Mac, press Command-Q to quit the assistant without completing setup. Then click Shut Down. When the new owner starts up the Mac, they can use their own information to complete setup.
Other macOS installation options
When you install macOS from Recovery, you get the current version of the most recently installed macOS, with some exceptions:
- On an Intel-based Mac: If you use Shift-Option-Command-R during startup, you're offered the macOS that came with your Mac, or the closest version still available. If you use Option-Command-R during startup, in most cases you're offered the latest macOS that is compatible with your Mac. Otherwise you're offered the macOS that came with your Mac, or the closest version still available.
- If the Mac logic board was just replaced, you may be offered only the latest macOS that is compatible with your Mac. If you just erased your entire startup disk, you may be offered only the macOS that came with your Mac, or the closest version still available.
You can also use these methods to install macOS, if the macOS is compatible with your Mac:
- Use the App Store to download and install the latest macOS.
- Use the App Store or a web browser to download and install an earlier macOS.
- Use a USB flash drive or other secondary volume to create a bootable installer.
Regular expressions is a powerful tool for solving many problems related to text. It can be misused as any good tool, but there are moments when they are the best solution for a given problem. At those moments the lack of regular expressions for Cocoa on Mac OS X and Cocoa Touch on iPhone OS is a pain in the butt.
Or are regular expressions really missing? Regular expressions can be used with NSPredicate that is part of Core Data, available since Mac OS X 10.4 and officially announced for iPhone OS 3.0. Cocoa's WebView and the equivalent UIWebView in Cocoa Touch both support JavaScript with regular expressions. So there sure is regular expressions available on the platforms, but how do you make it available for your own code?
An Ugly Solution
You can actually get access to the regular expression engine through JavaScript, unfortunately this requires a roundtrip through WebKit. On an iPhone this means you have to use an off-screen instance of UIWebView, and delegate execution of regular expression to it.
Nothing (erkberg) Mac Os Download
The complexity of an off-screen WebView or UIWebView could be hidden by a utility class. But the extra glue code needed to make something useful out of the single method stringByEvaluatingJavaScripFromString:, would be allot.
What Apple Recommends
For most problems the official stance is correct; do not use regular expressions. Instead use NSScanner, that is perfect for sequentially parse texts. It is very fast and can substitute any regular expressions that only relies on:
- Character sets
- Exact string matches
- Numerical matches
- Uniform input text
These conditions hold true to 95% of everything regular expressions is ever used for. For the other 5%, Apple leaves you to fend for your own.
Other Solutions
PCRE compiles perfectly with Cocoa, since it is written in C, one of the many advantages of Objective-C. PCRE is very capable, and almost a standard, but also very large. For an iPhone application the PCRE implementation could end up as the majority of your executables file-size. If this is something you can live with, then the open source RegexKit framework wraps PCRE in Cocoa and Cocoa Touch friendly Objective-C.
Mac Os Versions
Another regular expressions framework is OgreKit. The advantage of OgreKit is full unicode support, with the same disadvantage of size. And the fact that the documentation is in Japanese.
A Pretty Solution
You can also use these methods to install macOS, if the macOS is compatible with your Mac:
- Use the App Store to download and install the latest macOS.
- Use the App Store or a web browser to download and install an earlier macOS.
- Use a USB flash drive or other secondary volume to create a bootable installer.
Regular expressions is a powerful tool for solving many problems related to text. It can be misused as any good tool, but there are moments when they are the best solution for a given problem. At those moments the lack of regular expressions for Cocoa on Mac OS X and Cocoa Touch on iPhone OS is a pain in the butt.
Or are regular expressions really missing? Regular expressions can be used with NSPredicate that is part of Core Data, available since Mac OS X 10.4 and officially announced for iPhone OS 3.0. Cocoa's WebView and the equivalent UIWebView in Cocoa Touch both support JavaScript with regular expressions. So there sure is regular expressions available on the platforms, but how do you make it available for your own code?
An Ugly Solution
You can actually get access to the regular expression engine through JavaScript, unfortunately this requires a roundtrip through WebKit. On an iPhone this means you have to use an off-screen instance of UIWebView, and delegate execution of regular expression to it.
Nothing (erkberg) Mac Os Download
The complexity of an off-screen WebView or UIWebView could be hidden by a utility class. But the extra glue code needed to make something useful out of the single method stringByEvaluatingJavaScripFromString:, would be allot.
What Apple Recommends
For most problems the official stance is correct; do not use regular expressions. Instead use NSScanner, that is perfect for sequentially parse texts. It is very fast and can substitute any regular expressions that only relies on:
- Character sets
- Exact string matches
- Numerical matches
- Uniform input text
These conditions hold true to 95% of everything regular expressions is ever used for. For the other 5%, Apple leaves you to fend for your own.
Other Solutions
PCRE compiles perfectly with Cocoa, since it is written in C, one of the many advantages of Objective-C. PCRE is very capable, and almost a standard, but also very large. For an iPhone application the PCRE implementation could end up as the majority of your executables file-size. If this is something you can live with, then the open source RegexKit framework wraps PCRE in Cocoa and Cocoa Touch friendly Objective-C.
Mac Os Versions
Another regular expressions framework is OgreKit. The advantage of OgreKit is full unicode support, with the same disadvantage of size. And the fact that the documentation is in Japanese.
A Pretty Solution
It turns out that Mac OS X for years, and iPhone OS since inception, has been shipped with a perfectly good regular expressions engine. This engine is based on the ICU specification, so it works perfectly with unicode and is well on par with PCRE for functionality. This framework is simply called ICU Core, and has a C interface. But for a Cocoa programmers the C interface is not nice enough, and thankfully John Engelhart has done this work for us, with RegexKitLite. RegexKitLite is a little brother to RegexKit that wrapps ICU Core instead of PCRE.
RegexKitLite is published under BSD license, and is simply two files you add to your project, fully compatible with all available versions of both Mac OS X and iPhone OS. The tricky part is that ICU Core is not a public API officially supported by Apple, even though it has existed unchanged for years. Good news is that using ICU Core is not a show stopper for publishing on the iPhone App Store, application out there already uses it, both well known and not so well known.
Setting Up RegexKitLite
- Download the latest version from the sourceforge webpage, or SVN.
- Add
RegexKitLite.handRegexKitLite.mto your project. - Link your project against ICU Core, by adding the linker flag
-licucoreto Other Linker Flags under your projects build settings.
Optionally you can also add the documentation to Xcode with these easy steps:
- Open Help -> Documtantion.
- Press the Gears button in the lower left corder, and select New Subscription….
- Enter
feed://regexkit.sourceforge.net/RegexKitLiteDocSets.atomas URL.
Using RegexKitLite
This post is not a tutorial on regular expressions, but a tutorial on a partical API for executing regular expressions. If you want to learn more about regular expressions themselves I would recomend you look at Regular Expressions.info.
RegexKitLite provides it's functionality as categories on NSString and NSMutableString. This way using regular expressions with Cocoa is just as easy and normal string manipulation. This is best described using examples.
A simple example that normalizes a text with single white spaces, kind of like how a HML renderer would do, so this is handy when scraping web pages:
Or you can split a text, such as semi-colon delimeted data:
And you can extract more complex data using capture groups:
This may look like it could be slow to perform matches on the same regular expression twice, but it is not. RegexKitLite is very smart, and will cache your previous matches for very high performance.
RegexKitLite is a very capable, and also much active open source project, with version 3.0 as a release candidate in SVN. Use it, and use it well.
