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Display _something_ when an X app fails
When you run an X program from a terminal you can see any errors. But when it's run from another X program (eg from a menu item, from your fluxbox 'keys' file etc) it might just die and you see nothing (except perhaps in .xsession-errors). Instead, launch it via this command and you'll see the termination status, stderr and stdout. eg: "xlaunch firefox" or "xlaunch 'echo stdout; echo stderr >&2; false'": 'echo stdout; echo stderr >&2; false' failed with error 1 STDERR: stderr STDOUT: stdout

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Create cheap and easy index.html file
If your admin has disabled Apache's directory index feature but you want to have a cheap way to enable it for one folder, this command will just create an index.html file with a link to each file in the directory (including the index.html file, which is not ideal but makes the command much simpler). The HTML isn't even remotely compliant, but it could easily be improved on. Also, the command needs to be run each time a file is added or removed to update the index.html file.

du and sort to find the biggest directories in defined filesystem
I had the problem that our monitoring showed that the "/" filesystem is >90% full. This command helped me to find out fast which subdirs are the biggest. The system has many NFS-mounts therefore the -x.

Rename files in batch

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

SSH Auto-login with password
You need to install "sshpass" for this to work. apt-get install sshpass

Open Remote Desktop (RDP) from command line having a custom screen size
This example uses xfreerdp, which builds upon the development of rdesktop. This example usage will also send you the remote machine's sound.

Watch contents of a file grow
In this case, I'm keeping an eye on /var/log/messages, but of course any file will do. When I'm following a file, I generally don't want to see anything other than what has been added due to the command or service I've executed. This keeps everything clean and tidy for troubleshooting.

Use Vim to convert text to HTML.
``vimhtml somefile.txt`` will open vim for the HTML convertion and close it immediately after its done, leaving you with somefile.html which you can later use in your website or whatever.


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