Check These Out
`blkid` is an interface to libuuid - it can read Device Mapper, EVMS, LVM, MD, and regular block devices.
-c /dev/null - Do not use cached output from /etc/blkid.tab or /etc/blkid/blkid.tab (RHEL)
-i - Display I/O Limits (aka I/O topology) information (not available in RHEL)
-p - Low-level superblock probing mode (not available in RHEL)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"
ry4an@four:~$ echo $SHLVL
1
ry4an@four:~$ ${0/-/}
ry4an@four:~$ echo $SHLVL
2
"What it actually shows is going to be dependent on the commands you've previously entered.
When you do this, bash looks for the last command that you entered that contains the substring "ls", in my case that was "lsof ...". If the command that bash finds is what you're looking for, just hit Enter to execute it. You can also edit the command to suit your current needs before executing it (use the left and right arrow keys to move through it).
If you're looking for a different command, hit Ctrl+R again to find a matching command further back in the command history. You can also continue to type a longer substring to refine the search, since searching is incremental.
Note that the substring you enter is searched for throughout the command, not just at the beginning of the command." - http://www.linuxjournal.com/content/using-bash-history-more-efficiently
This is the same command as this one, but for OS X.
http://www.commandlinefu.com/commands/view/3053/find-out-when-your-billion-second-anniversary-is-was.
Admittedly, I'd never have thought of this without the earlier examples, but here's one that you can execute from your workstation to just display the image from another, without separately doing a file transfer, etc. By the way, I hear a loud beep coming from the other room, so I guess it's not too stealthy :-D
This function make it easy to compute X/Y as a percentage.
The name "wpoxiy" is an acronym of "what percentage of X is Y"