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Adding formatting to an xml document for easier reading
This will indent the input to be more readable. Warnings and messages are not send to STDOUT so you can just use a pipe to create the formatted outputfile, like: $ tidy -i -xml in.xml > out.xml

SSH connection through host in the middle

Display the number of connections to a MySQL Database
Count the number of active connections to a MySQL database. The MySQL command "show processlist" gives a list of all the active clients. However, by using the processlist table, in the information_schema database, we can sort and count the results within MySQL.

small CPU benchmark with PI, bc and time.
$ # 4 cores with 2500 pi digits $ CPUBENCH 4 2500 $. $ every core will use 100% cpu and you can see how fast they calculate it. $ if you do 50000 digitits and more it can take hours or days

prints line numbers
the sed way to print line numbers

Show IP Address in prompt --> PS1 var
when working with many machines in a computer lab need to know the IP addr is very large, this is a simplistic solution to make things easier

generate random mac address

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Search trought pidgin's conversation logs for "searchterm", and output the result.
will search trought pidgin conversation logs for "searchterm", and output them stripping the html tags. The "sed" command is optionnal if your logs are stored in plain text format.


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