'Too many open files' error xcode

Check if you have too many open simulators. I closed all the simulators and the error went away

I think you just have reached the maximum number of open file descriptors.

You can check the limit by

$ ulimit

And change it by:

$ ulimit -n 6666

But do not forget ulimit changes the limit only for current session. You have to put ulimit -n 6666 to .bash_profile or something like this

Check the number of file descriptors that can be opened by your shell. Most cases, default will be 256.

ulimit -a

To solve the 'too many open files' issue locally, increase the number of files that can be opened per shell:

ulimit -S -n 2048 #2048 works fine, or you may put other value.

In case it still does not resolve, system settings can be checked the following way:

sysctl kern.maxfiles sysctl kern.maxfilesperproc

If you prefer to increase the limits system wide, go for these:

sysctl -w kern.maxfiles=20480 (or any number) sysctl -w kern.maxfilesperproc=18000 (or any number)

Use sudo at the beginning of the command, in case you get permission denied.

In order to make this a permanent setting, you will need to add it or change default kernal parameters in /etc/sysctl.conf file.

This article explains the details.