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similar to the previous command, but with more friendly output (tested on linux)
Shows a tree view of parent to child processes in the output of ps (linux). Similar output can be achieved with pstree (also linux) or ptree (Solaris).
Or "tail -r" on Solaris.
the newest rpms are at the top; individual packages can also be queried this way:
rpm --last -q package
Uses lsof to list open network connections (file descriptors), grepping for only those in an established state
remotely connects to an https site, fetches the ssl certificate and displays the valid dates for the cert
bash/ksh subshell redirection (as file descriptors) used as input to diff