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yum -q list updates | tail -n+2

Find the package that installed a command

Give any files that don't already have it group read permission under the current folder (recursive)
Makes any files in the current directory (and any sub-directories) group-readable. Using the "! -perm /g=r" limits the number of files to only those that do not already have this property Using "+" on the end of the -exec body tells find to build the entire command by appending all matching files before execution, so invokes chmod once only, not once per file.

Make sure your script runs with a minimum Bash version
If you use new features of a certain Bash version in your shell script, make sure that it actually runs with the required version.

Rename files in batch

Query ip pools based on successive netnames via whois
Useful if you f.i. want to block/allow all connections from a certain provider which uses successive netnames for his ip blocks. In this example I used the german Deutsche Telekom which has DTAG-DIAL followed by a number as netname for the dial in pools. There are - as always ;) - different ways to do this. If you have seq available you can use $ net=DTAG-DIAL ; for i in `seq 1 30`; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done or without seq you can use bash brace expansion $ net=DTAG-DIAL ; for i in {1..30}; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done or if you like while better than for use something like $ net=DTAG-DIAL ; i=1 ; while true ; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; test $i = 30 && break ; i=$(expr $i + 1) ; done and so on.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Show git branches by date - useful for showing active branches

To find which host made maximum number of specific tcp connections
This command is primarily going to work on linux boxes. and needs to be changed, for example IP=10\.194\.194\.2 PORT=389

Convert multiple flac files to mp3
make sure that flac and lame are installed sudo apt-get install lame flac


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