Check all socket opened in linux OS

Question

The below command opens the socket with this function:

sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP)

After sending data the socket gets closed:

close(sockfd);

But this issue is when my program doesn't run well and is blocking. Thereby this socket will not be closed.

How can I check any sockets opened under Linux OS?

Answer 1

Use the below command:

/proc/net/tcp -a list of open tcp sockets

/proc/net/udp -a list of open udp sockets

/proc/net/raw -a list all the 'raw' sockets

These are some files, use the cat command to view them. For example:

cat /proc/net/tcp

You can also use the lsof command.

lsof is the command to open list files, which is used under various Unix-like systems to report your list of all open files and these methods that opened them.

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