Steps for creating an ancillary socket

This topic describes the steps of creating an ancillary socket.

Before you begin

Ensure that the ancillary socket is not closed until all stream sockets that might reference those shared memory objects are closed. This can be accomplished by taking advantage of the fact that the UNIX System Services process cleanup service closes sockets sequentially from lowest-numbered socket descriptor to highest-numbered socket descriptor.

Procedure

Perform the following steps:

Issue a getrlimits() request to discover the largest socket descriptor available for the process.
Issue a dup2() request to copy the original ancillary socket descriptor to the largest socket descriptor obtained from the getrlimits() request.
Close the original ancillary socket descriptor.