Linux tooltips

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If you have time, visit the site. It contains very much information about Linux and very much more.

Basic help

finding more information
Howto read a manual page?
use man: man COMMAND
Where COMMAND is the command for which you want to gather help.

Advanced help

file processing
Howto substitute umlauts in a textfile?
use sed: sed "s/ä/ae/g;s/ü/ue/g;s/ö/oe/g;s/ß/ss/g" FILENAME_OLD > FILENAME_NEW
Howto find strings in many files?
use grep: grep -Rn "STRING" *
Howto backup an entire directory?
use rsync: rsync -mavvhh --progress --exclude-from=FILE --checksum --link-dest=LASTBACKUPDIR /PATH/TO/DIR/WHICH/SHOULD/BE/BACKED/UP/ /BACKUPSTORAGEDIR/DATE

here is an example: it is a shell script which copies my homedir to a safe place

nice to know

Howto disable the system beep?
use xset: xset b off