ionic build ios command not working - ionic-framework

Question

I have walked through the tutorial instructions to set up cordova and ionic. I can successfully run the app in development but get this error when building ios. Any ideas? Tried updating node and cordova.
sudo ionic build ios
Running 'build:before' gulp task before build
[11:16:00] Starting 'clean'...
[11:16:00] Finished 'clean' after 47 ms
[11:16:00] Starting 'build'...
[11:16:00] Starting 'sass'...
[11:16:00] Starting 'html'...
[11:16:00] Starting 'fonts'...
[11:16:00] Starting 'scripts'...
[11:16:00] Finished 'scripts' after 45 ms
[11:16:00] Finished 'html' after 51 ms
[11:16:00] Finished 'fonts' after 54 ms
[11:16:00] Finished 'sass' after 770 ms
[11:16:07] Finished 'build' after 7.18 s
[11:16:07] Starting 'build:before'...
[11:16:07] Finished 'build:before' after 11 μs
• You're trying to build for ios but don't have the platform installed yet.
∆ Installing ios for you.
Installing cordova-plugin-device
Installing cordova-plugin-console
Installing cordova-plugin-whitelist
Installing cordova-plugin-splashscreen
Installing cordova-plugin-statusbar
Installing ionic-plugin-keyboard
Error: Command failed: /bin/sh -c cordova platform add ios
Error: Platform ios already added.
at ChildProcess.exithandler (child_process.js:213:12)
at emitTwo (events.js:87:13)
at ChildProcess.emit (events.js:172:7)
at maybeClose (internal/child_process.js:821:16)
at Socket.<anonymous> (internal/child_process.js:319:11)
at emitOne (events.js:77:13)
at Socket.emit (events.js:169:7)
at Pipe._onclose (net.js:4
69:12)

Answer 1

First of all, it seems you have some issues on ios platform installation, try removing it and adding it back to your development space.
Run command ionic platform remove ios && ionic platform add ios before trying to build for ios.
Second, you need Mac Operating system to build ios apps, as it has dependencies on XCode (A native software) to build.
Third, if you still have the same iussue, then it could be due to a bug discribed here. https://github.com/driftyco/ionic-cli/issues/772
Try sudo npm install -g cordova and rerun the build.
Good luck.