Commands by tamouse (7)

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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.

temporarily override alias of any command
say, someone has aliased ls to 'ls --color=always' and you want to temporarily override the alias (it does not override functions)

Determine next available UID
Typical usage would be in a script that would want the next open UID in a range (in this case 500-600)

Convert flv without re-encoding

display typedefs, structs, unions and functions provided by a header file
will display typedefs, structs, unions and functions declared in 'stdio.h'(checkout _IO_FILE structure). It will be helpful if we want to know what a particular header file will offer to us. Command 'cpp' is GNU's C Preprocessor.

Count number of files in a directory
Just want to post a Perl alternative. Does not count hidden files ('.' ones).

Display summary of git commit ids and messages for a given branch
In color. Additionally you may define in your ~/.gitconfig and run it just as 'git one': one = log --pretty='format:%Cgreen%H %Cred%ai %Creset- %s'

convert ascii string to hex
just a bit simpler

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"

create random string from /dev/urandom (or another length)


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