Commands by djpohly (1)

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Remove blank lines from a file using grep and save output to new file

determine if tcp port is open
@putnamhill, no need if statement in that case. && is a AND and || is a OR

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

list block devices
Shows all block devices in a tree with descruptions of what they are.

Find size in kilobyte of files that are deleted but still in use and therefore consumes diskspace

Convert spaces in file names to underscores

Get a stream feed from a Twitter user
*** CAREFULLY READ THE NOTES **** *** THIS DOES NOT WORK "OUT OF THE BOX" *** You'll need a few minutes of CAREFUL reading before making your own Twitter feed: In 2010 simple command line Twitter feed requests all stopped working because Twitter upgraded to SSL security. Https requests for a filtered Twitter stream feed now require a special header called "oauth_header". The benefit is that your stream feed and login info is securely encrypted. The bad news is that an "oauth_header" takes some work to build. Fortunately, four functions, imaginatively named step1, step2, step3 and step4 can be used to build a customized oauth_header for you in a few minutes. Now, go look at "step1" to start creating your own oauth_header!

Copy specific files recursively using the same tree organization.
This command has been used to overwrite corrupted "entries" files of a corrupted subversion working copy. Note the --files-from input format.

Lists all usernames in alphabetical order

Set name of windows in tmux/byobu to hostnames of servers you're connected to
*I run this with byobu as as a custom status bar entry that runs every 10 seconds by putting it in a script here: $ .byobu/bin/10_update_windows There's no output to stdout, so nothing is displayed on the status bar. *Presumes that #{pane_title} is set to the hostname or prompt containing the host name. In my case, it's in this format: $ [email protected]$HOSTNAME:$PWD The sed commands may need to be modified if your pane_title is different. *If you want to strip out a common part of a hostname, add the following before '| uniq' $ -e 's/[COMMON PART]//' I use that to strip out the domain of the servers I connect to, leaving the subdomain.


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