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hanukkah colored bash prompt
blue and yellow colored bash prompt for a Hanukkah celebration on your box

Transform a portrait pdf in a landscape one with 2 pages per page
This is an example of the usage of pdfnup (you can find it in the 'pdfjam' package). With this command you can save ink/toner and paper (and thus trees!) when you print a pdf. This tools are very configurable, and you can make also 2x2, 3x2, 2x3 layouts, and more (the limit is your fantasy and the resolution of the printer :-) You must have installed pdfjam, pdflatex, and the LaTeX pdfpages package in your box.

Perl One Liner to Generate a Random IP Address

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" }

tar directory and compress it with showing progress and Disk IO limits
tar directory and compress it with showing progress and Disk IO limits. Pipe Viewer can be used to view the progress of the task, Besides, he can limit the disk IO, especially useful for running Servers.

Execute a command with a timeout
In this example the command "somecommand" will be executed and sent a SIGALARM signal if it runs for more than 10 seconds. It uses the perl alarm function. It's not 100% accurate on timing, but close enough. I found this really useful when executing scripts and commands that I knew might hang E.g. ones that connect to services that might not be running. Importantly this can be used within a sequential script. The command will not release control until either the command completes or the timeout is hit.

Delete all non-printing characters from a file
tr has some predefined sets of characters that are more convenient to use than characters codes

Explanation of system and MySQL error codes
perror should be installed if mysql-server package is installed

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

ptree equivalent in HP-UX
By setting the UNIX95 variable in HP-UX the XPG4 mode is activated, you get new options for ps and other commands, for me the best way to use this is to create an alias named ptree in root profile: alias ptree='UNIX95=1 ps -eH'


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