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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 the total number of changes that every user committed to a Subversion repository
This saves Subversion's log output as XML and then runs an XQuery over it. This is standard XQuery 1.0 and should therefore also work with other XQuery processors. I have tested it with Zorba (http://www.zorba-xquery.com). XQilla (http://xqilla.sourceforge.net) also does it, but you'd have to save the query to a file and then execute "xqilla filename.xq". The query first finds all distinct authors and then, for each author, sums up the number of paths they have changed in each commit. This accounts for commits of multiple changes at once. The indenting space in all lines from the second one seems to be due to a bug in Zorba.

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"

Do some learning...
no loop, only one call of grep, scrollable ("less is more", more or less...)

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

a function to find the fastest free DNS server
Evoke from the command like as: $ timeDNS commandlinefu.com . This isn't too terribly practical, but it is a good code example of using subshells to run the queries in parallel and the use of an "anonymous function" (a/k/a "inline group") to group i/o. . I'm assuming you have already defined your local DNS cache as ${local_DNS}, (here, it's 192.168.0.1). . You do need to install `moreutils` to get `sponge`. . If you're willing to wait, a slower version w/o sponge, (and w/o sorting), is this: . DNS () { for x in "192.168.0.1" "208.67.222.222" "208.67.220.220" "198.153.192.1" "198.153.194.1" "156.154.70.1" "156.154.71.1" "8.8.8.8" "8.8.4.4"; do (echo -n "$x "; dig @"$x" "$*"|grep Query) ; done ; }

Create a new file

Extract public key from private
This will extract the public key that is stored in the private key using openssl.

clean up memory on linux
where proc filesystem mounted under /proc

Every Nth line position # (SED)
sed extract every nth line. Generic is: $ sed -n 'STARTPOSITION,${p;n;*LINE}' foo where n;*LINE = how many lines. thus p;n;n; is "for every 3 lines" and p;n;n;n;n; is "for every 5 lines"


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