In macOS 10.15 and higher, iTunes has been replaced with the Music app. This requires that the Media Synchronization Tool access the library in a different way than it has done previously. To support the new method, the sync tool depends on swift, an open source programming language championed by Apple. This dependency is carried by macOS’s Command Line Tools package. The sync tool will detect that this dependency is not met and attempt to install it on behalf of the user. macOS will present a prompt to perform this operation. If there is an issue during installation, the sync tool will be unable to continue and present this article for further troubleshooting. It is likely the case that the dependency can be manually installed. To manually install the Command Line Tools, follow these steps:
Open Terminal.app, found at
/Applications/Utilities/Terminal.appAny terminal emulator will do, this one is included in macOS
At the command prompt, enter
sudo xcode-select --installAt the password prompt, enter the password for the user account on the computer and then press enter.
For security purposes, there may not be characters onscreen as the password is typed.
macOS will launch the installer for the tools. Follow its prompts.
This installer will download and install the tools. It takes about 5 minutes for the whole process with 100Mb/s internet.
The sync tool will detect when the installation is complete and continue launching.
For consistency, we now use this new method to interface with the music library as far back as it is supported on macOS, which is on any macOS versioned 10.13 or higher. On earlier versions (macOS 10.10-10.12), we continue to read the iTunes XML file provided by iTunes under those versions of macOS, given that the setting is enabled in iTunes. For assistance enabling this, please see https://autonomic.atlassian.net/l/c/iPQy9o4s. On those earlier versions, the dependency on swift is neither required by the sync tool nor available from Apple.