Commands by schef (2)

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Find out when your billion-second anniversary is (was).
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.

Search some text from all files inside a directory

Clear filesystem memory cache
Found here: http://ubuntuforums.org/showthread.php?t=589975

Press ctrl+r in a bash shell and type a few letters of a previous command
In the sample output, I pressed ctrl+r and typed the letters las. I can't imagine how much typing this has saved me.

Find brute force attempts on SSHd
Searches the /var/log/secure log file for Failed and/or invalid user log in attempts.

Read null character seperated fields from a file
Handle any bad named file which contains ",',\n,\b,\t,` etc Store the file name as null character separated list $find . -print0 >name.lst and retrieve it using $read -r -d "" Eg: $find . -print0 >name.lst; $cat name.lst| while IFS="" read -r -d "" file; $do $ls -l "$file"; $done

see who's using DOM storage a/k/a Web Storage, super cookies
Someone over at Mozilla dot Org probably said, "I know, let's create a super-duper universal replacement for browser cookies that are persistent and even more creepy and then NOT give our browser users the tools they need to monitor, read, block or selectively remove them!" . This will let you see all the DOM object users in all your firefox profiles. Feel free to toss a `| sort -u` on the end to remove dupes. . I highly recommend you treat these as "session cookies" by scripting something that deletes this sqlite database during each firefox start-up. . note: does not do anything for so-called "flash cookies"

Perl one-liner to determine number of days since the Unix epoch
There are some environments that use this value for password and account expiration. It's helpful to be able to quickly determine the number of days since the Unix epoch (dse) when working directly with the configuration files as an administrator.

Debian: Mark all dependent packages as manualy installed.
Debian: Mark all dependent packages as manually installed. So they are not automatically removed if you remove some meta package - like gnome-desktop-environment for example.

Remove all old kernels
http://askubuntu.com/questions/89710/how-do-i-free-up-more-space-in-boot

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