Difference between revisions of "How Do I: A Macintosh OSX Q&A"

Revision as of 09:36, 20 June 2020

User Questions

Q: Run Multiple Instances of an Application

There are a number of workaround for this problem with OSX. Apple designed OS X to behave like the System 7, Mac OS 7.6 days whereas a program uses a single unified system interface and only one will launch at a time. The interesting thing is that this is not a kernel level restriction since OSX is built on FreeBSD and therefore the underlying system supports launching multiple instances of a program.

Answer #1 - Use the command line. Running a program with the "-n" flag tells the system to open a new instance of the same program application.

open -n -a "APPLICATION NAME"

example:

open -n -a /Applications/Safari.app/

Answer #2 - Create a copy of the program with a different name and run each individually. This is less desirable because you end up with disk space wasted in having several copies of the same software on the disk.

Answer #3 - create a 2nd user account on your Mac. You can have the app open in both accounts, signed in to different accounts. If you enable fast switching, you can very quickly switch between the two."

Some software will not behave correctly when running multiple instances of it at the same time. This has to do with how the software may cache data, or save configuration files. In some cases one of the three methods above might work better than another. Each method has limitations. The best method is Answer #1 for most general applications.

Q: Enable SSH Server (Remote Login) on Mac

Method One: in MacOS Mojave 10.14, MacOS High Sierra 10.13, macOS Sierra 10.12, OS X El Capitan 10.11, Yosemite 10.10, OS X Mavericks 10.9, 10.8 Mountain Lion, 10.7 Lion, and 10.6 Snow Leopard.

1. Open System Preferences from the Apple menu, and click on the “Sharing” preference panel
2. Select the checkbox next to “Remote Login” to enable it, like the screenshot indicates
3. Clicking the checkbox will instantly start the various remote login servers, including sftp and ssh.

Method Two: Using the command line. turn on SSH server and allow incoming ssh connections use the -setremotelogin flag with systemsetup

sudo systemsetup -setremotelogin on

to disable SSH servers from the command line

sudo systemsetup -setremotelogin off

To skip prompts

sudo systemsetup -f -setremotelogin off
systemsetup -f -setremotelogin on

When you connect first time you will see

The default interactive shell is now zsh.
To update your account to use zsh, please run `chsh -s /bin/zsh`.
For more details, please visit https://support.apple.com/kb/HT208050.

Q: Enable VNC Server (Remote Desktop) on Mac

Apple includes a VNC server in every edition of Mac OS X 10.4 and later.

Enable Apple Remote Desktop within the Services panel.

Or from the command prompt

enable screen sharing with a specified password:

sudo /System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/Resources/kickstart -activate -configure -access -on -clientopts -setvnclegacy -vnclegacy yes -clientopts -setvncpw -vncpw password1 -restart -agent -privs -all

command to disable screen sharing:

sudo /System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/Resources/kickstart -deactivate -configure -access -off