Commands by tatgren (1)

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Get info on RAM Slots and Max RAM.

Find the package that installed a command

Tell what is encoded in a float, given its HEX bytes
It handles all possible combination of the hex bytes, including NaNs, Infinities, Normalized and Subnormal Numbers... $ This crazy DC stuff spent me a few days to write, optimize, polish and squeeze so that it works within the tight 255 character bound... $ You can modify it easily for other IEEE754 numbers, say, half, double, double-extended, quadruple $ (I hope someone will find this useful and submit more dc code to commandlinefu!)

killall -r ".*my-process.*"

Get Hardware UUID in Mac OS X
Formats the output from `ioreg` into XML, then parses the XML with `xmllint`'s xpath feature.

Split and join with split and cat.
`split -b 1k file` splits files into 1k chunks. Rejoin them with `cat x* > file`.

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"

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

Creates PodFeeds.txt, a file that lists the URLs of rhythmbox podcasts from the rhythmdb.xml file.
The first grep any line with pod-feed in it plus the following five lines. The second grep throws out any line not containing . sed removes the leading four spaces then and the trailing . Using a colon as sed's separating character avoids having to escape the /. Works ok with Mythbuntu 9.04 (used mostly as a three line bash script).

Using awk to sum/count a column of numbers.
Takes a input file (count.txt) that looks like: 1 2 3 4 5 It will add/sum the first column of numbers.


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