npm install error

i can install npm but this error will be genrate.

'sed' is not recognized as an internal or external command,
operable program or batch file.
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! VoximplantDemo@0.0.1 postinstall: sed -i '' 's/\/Core//g' ./node_modules/react-native-voip-push-notification/RNVoipPushNotification.podspec; sed -i '' 's/\/Core//g' ./node_modules/react-native-callkeep/RNCallKeep.podspec
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the VoximplantDemo@0.0.1 postinstall script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\davea\AppData\Roaming\npm-cache_logs\2019-11-28T05_24_59_147Z-debug.log

+1 facing the same issue on windows.

Hello!

If you use windows, please remove this line:

react-native-demo/package.json

Line 7 in e36c4c4

    
           "postinstall": "sed -i '' 's/\\/Core//g' ./node_modules/react-native-voip-push-notification/RNVoipPushNotification.podspec; sed -i '' 's/\\/Core//g' ./node_modules/react-native-callkeep/RNCallKeep.podspec",

This line introduce a workaround for third-party dependencies that are used in the demo project for iOS platform.

Best regards,
Yulia Grigorieva

i also facing same issue

do you have any possible solution please share it thank