react-native-xcode.sh doesn't filter out link local addresses correctly

[msbit]

Description

At

react-native/packages/react-native/scripts/react-native-xcode.sh

Lines 17 to 22 in 63e893d

	for num in 0 1 2 3 4 5 6 7 8; do
	IP=$(ipconfig getifaddr en${num} || echo "")
	if [ ! -z "$IP" ]; then
	break
	fi
	done

the script goes through a list of interfaces looking for an IP, using ipconfig getifaddr.

At

react-native/packages/react-native/scripts/react-native-xcode.sh

Lines 23 to 25 in 63e893d

	if [ -z "$IP" ]; then
	IP=$(ifconfig | grep 'inet ' | grep -v ' 127.' | grep -v ' 169.254.' |cut -d\ -f2 | awk 'NR==1{print $1}')
	fi

if the previous search hasn't found anything (IP is empty) it uses a looser search, grepping for inet and discarding link local addresses (127.x and 169.254.x).

The scenario I have is where my en0 has a link local address (169.254.36.33) and so as the first search doesn't filter out these addresses, this is what is written to ip.txt at

react-native/packages/react-native/scripts/react-native-xcode.sh

Line 27 in 63e893d

echo "$IP" > "$DEST/ip.txt"

and so my iOS device cannot connect to the metro instance.

Steps to reproduce

React Native Version

0.74.1

Affected Platforms

Runtime - iOS

Output of npx react-native info

-

Stacktrace or Logs

-

Reproducer

Screenshots and Videos

No response

[github-actions]

⚠️	Missing Reproducible Example
ℹ️	We could not detect a reproducible example in your issue report. Please provide either: If your bug is UI related: a Snack If your bug is build/update related: use our Reproducer Template. A reproducer needs to be in a GitHub repository under your username.

[github-actions]

⚠️	Add or Reformat Version Info
ℹ️	We could not find or parse the version number of React Native in your issue report. Please use the template, and report your version including major, minor, and patch numbers - e.g. 0.70.2

[cortinico]

cc @cipolleschi @robhogan et al. if we need to fix this in a different way for iOS

[cipolleschi]

@msbit you have issues with your physical device only, right? It works properly on the simulator, correct?

[msbit]

@cipolleschi I haven't checked explicitly, but I'm guessing the check of platform at:

react-native/packages/react-native/scripts/react-native-xcode.sh

Line 16 in 63e893d

if [[ ! "$SKIP_BUNDLING_METRO_IP" && "$CONFIGURATION" = *Debug* && ! "$PLATFORM_NAME" == *simulator ]]; then

would exclude this behaviour under simulators.

[cipolleschi]

yes, it is possible. @robhogan could you take this? I'm going to be on PTO next week. Otherwise I can look into it when I'm back.