How can i match each /proc/net/tcp entry to each opened socket?

c linux networking procfs
Manuel Abeledo picture Manuel Abeledo · Jul 23, 2010 · Viewed 19.3k times · Source

I'm trying to parse socket info from /proc/net/tcp and while I can identify some fields, such as memory addresses or send queue use, I can't find how each entry is bound to its socket descriptor. e.g., with this data:

1: 5922140A:E459 D5C43B45:0050 01 00000000:00000000 00:00000000 00000000  1000        0 507218 1 f6ab1300 57 3 12 4 -1

I want to know which is the correspondant socket descriptor.

Answer

caf picture caf · Jul 25, 2010

Take the inode number (in this case, 507218). Each open file descriptor to that socket (there may be multiple file descriptors for the same socket) will appear as a link of the form:

/proc/<PID>/fd/<N> -> socket[507218]

(where <PID> is the process ID and <N> is the file descriptor).

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