Difference in behaviour between getifaddrs() and ioctl(SIOCGIFCONF)

[Jason Curl]

Hello,

I've seen an issue when using getifaddrs() using Cygwin 1.7.x (snapshot 
build from 2010-11-24, shortly after the ARP fixes from Corinna). 
Operating System is Windows 7 x64_86 Ultimate.

When I use getifaddrs() I get a list of interface names, some are 
appended with ":1".

Getting the list with ioctl(SIOCGIFCONF) provides a different list of 
names, where interface names only differ sometimes by ":1".

The list from ioctl() is correct, that from getifaddrs() is incorrect, 
in that the name cannot be used to resolve the HWADDR, SIOCGIFFRNDLYNAM 
with ioctl().

Using getifaddrs():
device: {4ED54D4E-1024-4BDF-A926-67D2895D2DC4}; 
ioctl(SIOCGIFFRNDLYNAM)=0 Local Area Connection 4
device: {A045DC0F-A979-49B3-954C-D0678365FF26}:1; ioctl(SIOCGIFFRNDLYNAM)=-1
device: {4EB69B61-C791-434A-8FCE-8F4859EA8DFC}; 
ioctl(SIOCGIFFRNDLYNAM)=0 Local Area Connection 3
device: {85C2CEC7-A2B9-47D4-9A50-D63E9F9ED007}; 
ioctl(SIOCGIFFRNDLYNAM)=0 Bluetooth Network Connection
device: {56D2E68A-4173-4117-A719-65123B973C65}:1; ioctl(SIOCGIFFRNDLYNAM)=-1
device: {7E5203E8-97DE-4822-9A2E-380BD258D97E}:1; ioctl(SIOCGIFFRNDLYNAM)=-1
device: {8424F604-4FAE-4541-9D8E-7B0A583A0956}:1; ioctl(SIOCGIFFRNDLYNAM)=-1
device: {846EE342-7039-11DE-9D20-806E6F6E6963}:1; ioctl(SIOCGIFFRNDLYNAM)=-1


Using ioctl(SIOCGIFCONF):
device: {4ED54D4E-1024-4BDF-A926-67D2895D2DC4}; 
ioctl(SIOCGIFFRNDLYNAM)=0 Local Area Connection 4
device: {A045DC0F-A979-49B3-954C-D0678365FF26}; 
ioctl(SIOCGIFFRNDLYNAM)=0 Bluetooth Network Connection 2
device: {4EB69B61-C791-434A-8FCE-8F4859EA8DFC}; 
ioctl(SIOCGIFFRNDLYNAM)=0 Local Area Connection 3
device: {85C2CEC7-A2B9-47D4-9A50-D63E9F9ED007}; 
ioctl(SIOCGIFFRNDLYNAM)=0 Bluetooth Network Connection
device: {56D2E68A-4173-4117-A719-65123B973C65}; 
ioctl(SIOCGIFFRNDLYNAM)=0 Local Area Connection
device: {7E5203E8-97DE-4822-9A2E-380BD258D97E}; 
ioctl(SIOCGIFFRNDLYNAM)=0 VMware Network Adapter VMnet1
device: {8424F604-4FAE-4541-9D8E-7B0A583A0956}; 
ioctl(SIOCGIFFRNDLYNAM)=0 VMware Network Adapter VMnet8
device: {846EE342-7039-11DE-9D20-806E6F6E6963}; 
ioctl(SIOCGIFFRNDLYNAM)=0 Loopback Pseudo-Interface 1


My control panel shows only interfaces
* Bluetooth Network Connection 2
* Local Area Connection
* VMware Network Adapter VMnet1
* VMware Network Adapter VMnet8


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