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Export all Mailman mailing lists Members to separate .txt files
Export all Mailman mailing lists Members to separate .txt files excluding "Mailman" and "Test" or add yours by && $1!="myDontWannaList"

how many pages will my text files print on?
This gives a very rough estimate of how many pages your text files will print on. Assumes 60 lines per page, and does not take long lines into account.

Pick a random line from a file
This is from perldoc -q random.*line, which says: This has a significant advantage in space over reading the whole file in. You can find a proof of this method in The Art of Computer Programming, Volume 2, Section 3.4.2, by Donald E. Knuth. Who am I to argue with Don Knuth?

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

Hide the name of a process listed in the `ps` output
$ exec -a $NAME $COMMAND $ARGS `your_cmd -erase_all_files` is the real process, but harmless-looking getty appears in the process table. Never actually had a need to do this, but interesting nonetheless... Tested in bash, dash. $ -a $NAME "pass NAME as the zeroth argument to COMMAND", i.e. customise the name of the process (as commonly seen with `ps`)

extract element of xml

SoX recording audio and trimming silence
Records audio from your mic in FLAC (Free Lossless Audio Codec) format, starts only after it detects at least 0.1 seconds of noise and stops after 1 second of silence. You can adjust the percent values (sensitivity) to best fit your microphone and voice (0.1% if you have a great quality mic, higher if you don't, 0% does not trim anything). Useful for speech recognition in conjunction with my previous command titled 'Google voice recognition "API"' (http://www.commandlinefu.com/commands/view/8043/google-voice-recognition-api).

Customize time format of 'ls -l'
the --time-style argument to 'ls' takes several possible modifiers: full-iso, long-iso, iso, locale, +FORMAT. The +FORMAT modifier uses the same syntax as date +FORMAT. --time-style=+"%Y-%m-%d %H:%M:%S" strikes a happy medium between accuracy and verbosity: $ ls -lart --time-style=long-iso doesn't show time down to the nearest second, $ ls -lart --time-style=full-iso displays time to 10E-9 second resolution, but with no significant digits past the full seconds, also showing the timezone: $ -rw-r--r-- 1 bchittenden bchittenden 0 2011-02-10 12:07:55.000000000 -0500 bar

return external ip
Get your ip address, hostname, ASN and geolocation information. If you want just one field as a text response you can also get that,eg curl ipinfo.io/ip


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