MacOS: Launch Local Application Telnet Error – Could not create a new process and open a pseudo-tty

MacOS: Launch Local Application Telnet Error – Could not create a new process and open a pseudo-tty

Note: For a better comprehension of this article and features, please check the Manual entry before reading.

NG5 Manual entry:

  • Console-like Access

  • Launch Local Application feature;

Launch Local Application with the Telnet command uses the URL telnet://IP_ADDRESS which is interpreted by the browser to open the local OS terminal application.

Depending on the OS, the terminal command issued tries to open the directory /usr/sbin, we should guarantee the telnet application path linked to this directory.

This directory is protected per Apple SIP as mentioned here from MacOS X El Capitan or later versions.

Then, the telnet app path (which telnet) should be linked to /usr/sbin so the browser will be able to launch it.

The steps below are meant to allow MacOS open the telnet URL properly, using Recovery Mode and bash terminal.

Disable Apple SIP

Reboot and go to Recover:

  • Restart your Mac, after apple logo appears, press the keys CMD+r

When the GUI comes up:

  • Choose a language

  • Choose your User and log-in

On the top of the screen, select Utilities -> Terminal (see image below)




Inside the terminal application on bash, execute the commands below:

1csrutil disable 2reboot

Associate telnet path to browser URL

After rebooting your Mac with Apple SIP disabled, open the Terminal app and execute the followings:

1Mount file systems as below: (Note: After the reboot, you system will go back to read-write.) 2sudo mount -uw / 3 4Get current installed telnet application PATH, example: /usr/local/bin/telnet: 5which telnet 6 7Create symlink to telnet PATH 8sudo ln -s /usr/local/bin/telnet /usr/bin/

Enable Apple SIP

Restart your Mac and go on Recovery Mode (explained above)

On the top of the screen, select Utilities -> Terminal

Inside the terminal application on bash, execute the commands below:

1csrutil enable 2reboot

Done. Now you can use through your browser the telnet URL telnet://IP_ADDRESS.


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