Solution to the “Mac screensaver won’t start” problem
By Alvin Alexander. Last updated: November 13 2019
mac-os-x
recent posts related to the mac os x operating system
How to show the largest files under a directory on Mac OS X (Unix)
By Alvin Alexander. Last updated: December 23 2017
Here’s an example that shows how to find the largest files under a directory on MacOS and Linux/Unix systems.
A du/sort command to show the largest files under a directory on Mac OS X
The Unix/Linux command that worked for me on my MacOS system is this:
$ du -a * | sort -r -n | head -10
du is the disk usage command, and the -a flag says, “Display an entry for each file in a file hierarchy.” Then I use the sort command to sort the du output numerically and in reverse. After that, head -10 shows only the first ten lines of output. In the Music folder on my Mac the command and output look like this:
sed on macOS: How to append multiple lines of text to an HTML or XML file
By Alvin Alexander. Last updated: December 19 2017
As a brief note about the Linux/Unix sed command, today I learned how to append multiple lines of text to an HTML (or XML) file on macOS. The short answer is that I created a sed commands file named changes.sed with these contents:
How to change the Mac Terminal title from the command line
By Alvin Alexander. Last updated: July 17 2019
Mac Terminal FAQ: How can I change the title on the Mac Terminal app from the Mac/Unix command line?
I've been working on a project where I have three Mac Terminal tabs open at one time, and I found it was much easier to work this way when I changed the title on each Terminal window. This helped me easily identify what I was doing in each Terminal window.
Changing the Mac Terminal title
The basic escape sequence you need to change the Terminal title from the command line is this:
MacOS screen annotation/presentation software
By Alvin Alexander. Last updated: August 28 2017
I was going to write a little application to let me annotate my MacOS screen during presentations, but the Ink2Go product looks like it does exactly what I was thinking. As I’m creating a video presentation, such as when showing how to write some Scala or Android code, I want to be able to draw on the screen, such as writing text, arrows, circles, and boxes to highlight parts of the screen. Ink2Go looks like what I want.
Developing an OSX Application in Java
By Alvin Alexander. Last updated: August 16 2017
This is a good guide for things to be aware of when creating Mac/macOS applications using Java. It mostly includes a lot of information about the com.apple.eawt.AppEvent library/classes.
Apple: Maintaining Your Signing Identities and Certificates
By Alvin Alexander. Last updated: August 16 2017
As a note to self, this apple.com Maintaining Your Signing Identities and Certificates page contains information on signing identities, certificates, provisioning profiles, developer accounts, developer id certficates, the keychain access app, exporting certificates, and more.
MacOS/Java AppBundler error: NoSuchFileException: Info.plist
By Alvin Alexander. Last updated: August 14 2017
If you’re using the Oracle AppBundler to build a Mac/MacOS application bundle from a Java application and run into this error when running Ant:
NoSuchFileException: <directory path here> Info.plist
I have found that the problem is that I have not set and exported JAVA_HOME. To set and export JAVA_HOME on MacOS 10.12, I use this command in the shell script I use to build my Mac/Java app:
The macOS application signing process doesn’t sign all files
By Alvin Alexander. Last updated: August 13 2017
I was surprised to learn that when you sign a macOS application, the signing process doesn’t sign every file under the .app application directory. Here’s a quote from the Apple developer docs:
“Your app’s executable code is protected by its signature because the signature becomes invalid if any of the executable code in the app bundle changes. Note that resources such as images and nib files aren’t signed; therefore, a change to these files doesn’t invalidate the signature.”
Getting a Mac/Java app ready for Apple’s Mac App Store
By Alvin Alexander. Last updated: August 12 2017
Over the last two days I’ve gotten a Mac/Java app ready for Apple’s Mac App Store, including bundling the application as a macOS “.app” application bundle, and signing it so it can be submitted to the Store.
A relatively quick look at my browser history shows that I needed to hit over 260 URLs to get that done. As a wise professor once told me, “Keep learning, keep learning.”