How does Linux handle multiple sockets bound to the same port with `INADDR_ANY` and a specific IP address?

I’m developing a server application on Linux and have a question about socket binding behavior when using INADDR_ANY and specific IP addresses. My setup involves two sockets:

1. One socket bound to port 80 with INADDR_ANY, meaning it listens on all available IP addresses.
2. Another socket bound to port 80 on a specific IP address, 66.117.236.114.

My question is:

1. If a client attempts to connect to 66.117.236.114 on port 80, is there any possibility that the connection could be handled by the socket bound to INADDR_ANY instead of the one explicitly bound to 66.117.236.114?

2. I am also using the SO_REUSEADDR socket option on both sockets. Could this affect how the connections are routed, or is it purely related to allowing both sockets to bind to the same port without error?

Here is the relevant snippet of how I’m binding the sockets:

int sock1 = socket(AF_INET, SOCK_STREAM, 0);
int sock2 = socket(AF_INET, SOCK_STREAM, 0);

int optval = 1;
setsockopt(sock1, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval));
setsockopt(sock2, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval));

// Socket 1: Bind to INADDR_ANY (all interfaces)
struct sockaddr_in addr1;
addr1.sin_family = AF_INET;
addr1.sin_addr.s_addr = htonl(INADDR_ANY);
addr1.sin_port = htons(80);
bind(sock1, (struct sockaddr*)&addr1, sizeof(addr1));

// Socket 2: Bind to specific IP address
struct sockaddr_in addr2;
addr2.sin_family = AF_INET;
addr2.sin_addr.s_addr = inet_addr("66.117.236.114");
addr2.sin_port = htons(80);
bind(sock2, (struct sockaddr*)&addr2, sizeof(addr2));

What I’ve Learned So Far:

• The socket bound to INADDR_ANY listens on all available IPs, while the other socket only listens on 66.117.236.114.
• The SO_REUSEADDR option allows both sockets to bind to the same port without errors, but as far as I understand, it doesn’t control which socket handles incoming connections.

My Key Questions:

1. Is there any scenario where a connection targeting 66.117.236.114:80 could be handled by the INADDR_ANY socket?
2. What role does SO_REUSEADDR play here? Does it impact which socket handles incoming connections, or is it only relevant during the binding process?

Desired Behavior:

I want to ensure that any connections targeting 66.117.236.114:80 are always handled by the second socket (the one explicitly bound to that address), and connections to other IPs (e.g., 127.0.0.1:80) are handled by the INADDR_ANY socket.

Any clarification or confirmation of how Linux handles this would be greatly appreciated!

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