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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

Find removed files still in use via /proc
Oracle DBA remove some logfiles which are still open by the database and he is complaining the space has not been reclaimed? Use the above command to find out what PID needs to be stopped. Or alternatively recover the file via: $ cp /proc/pid/fd/filehandle /new/file.txt

Random number generation within a range N, here N=10

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" }

Replace Caps-lock with Control-key
You can return to defaults with "setxkbmap". More here: http://dailycli.blogspot.com/2009/12/xmodmap-replace-caps-lock-with-left.html

print a file on a single line
Example: you have a package.txt you want to install on a system. Instead of this: cat package.txt package1 package2 package3 You want it to cat out on one line so you can print "yum install package1 package2 package3"

Ping all hosts on 192.168.1.0/24
-b option takes the broadcast address.

A bash timer
Starts and shows a timer. banner command is a part of the sysvbanner package. Instead of the banner an echo or figlet commands could be used. Stop the timer with Ctrl-C and elapsed time will be shown as the result.

swap the java version being used
You have openjdk and sun java installed. Many of your java plugins will not work properly. Something called IcedTea (the java web plugin) keeps crashing. Run this and select sun java to use sun java.

Find out which debian package a command (executable) belongs to on debian-based distros
This revision to my command (command #8851) was called for when it failed to find the parent package of 'rlogin', which is really a deep symbolic link to /usr/bin/ssh. This revision fixes this newfound issue, while ensuring fixes of other older issues work too.


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