Commands by rocteur (1)

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File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Print number of mb of free ram
This will show the amount of physical RAM that is left unused by the system.

Remove security limitations from PDF documents using QPDF
Remove security restrictions from PDF documents using this very simple command on Linux and OSX. You need QPDF installed (http://qpdf.sourceforge.net/) for this to work.

Remove all cached images for icons related to your profile
Run inside Command Prompt (cmd.exe) as admin. Note that you must close explorer.exe first, and even so some files will not be deleted, will say "Access is denied." To definitely delete them enter with another admin user or from other operating system and access the drive.

find duplicate messages in a Maildir
# find assumes email files start with a number 1-9 # sed joins the lines starting with " " to the previous line # gawk print the received and from lines # sort according to the second field (received+from) # uniq print the duplicated filename # a message is viewed as duplicate if it is received at the same time as another message, and from the same person. The command was intended to be run under cron. If run in a terminal, mutt can be used: mutt -e "push otD~=xq" -f $folder

resolve hostname to IP our vice versa with less output
inverted version: resolveip -s 216.34.181.xxx freshmeat.net

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

Give all those pictures the same name format, trailing zeros please for the right order, offset to merge different collections of pictures
When you have different digital cameras, different people, friends and you want to merge all those pictures together, then you get files with same names or files with 3 and 4 digit numbers etc. The result is a mess if you copy it together into one directory. But if you can add an offset to the picture number and set the number of leading zeros in the file name's number then you can manage. OFFS != 0 and LZ the same as the files currently have is not supported. Or left as an exercise, hoho ;) I love NF="${NF/#+(0)/}",it looks like a magic bash spell.

Grab mp3 files from your favorite netcasts, mp3blog, or sites that often have good mp3s
This was gotten from http://www.veen.com/jeff/archives/000573.html. The line will grab all the mp3 files on the urls listed in text file sourceurls.txt (one url per line) . A much more complete breakdown of the line can be found at the web site mentioned above.

find files in a date range
Example above will recursively find files in current directory created/modified in 2010.


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