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Is it a terminal?
Oddly, the isatty(3) glibc C call doesn't have a direct analogue as a command 'isatty(1)'. All is not lost as you can use test(1). For example, your script might be run from a tty or from a GUI menu item but it needs to get user-input or give feedback. Now your script can test STDIN with 'isatty 0' or STDOUT with 'isatty 1' and use xmessage(1) if the tty is not available. The other way to test for this is with 'tty -s' - but that's only for STDIN.

When feeling down, this command helps
$ sudo apt-get install sl $ man sl

Serial console to a Vmware VM
Create a serial console with "socket (named pipe)" of "/tmp/socket", "from:server, to:virtual machine" in vmware player, etc.. gui. Run the above command after you have booted the guest OS (which should also be configured for serial console).

system beep off

Figure out your work output for the day
Figures out what has changed in the last 12 hours. Change the author to yourself, change the time since to whatever you want.

print crontab entries for all the users that actually have a crontab
This is how I list the crontab for all the users on a given system that actually have a crontab. You could wrap it with a function block and place it in your .profile or .bashrc for quick access. There's prolly a simpler way to do this. Discuss.

bash screensaver (scrolling ascii art with customizable message)
Displays a scrolling banner which loops until you hit Ctrl-C to terminate it. Make sure you finish your banner message with a space so it will loop nicely.

parted - scripted partitioning (of all multipathed SAN LUNs)
`multipath -ll` requires Device Mapper multipath.conf configuration. And of course, replace "3PARdata,VV" with your disk array's SCSI vendor,LUN name. - GPT partition table allows you to create >2TB partitions

Open up a man page as PDF (#OSX)
Simply pass an argument to the script to convert the manual page to a PDF: $man2pdf drutil

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

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