Commands by spiffwalker (6)

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df without line wrap on long FS name
-P uses the POSIX output format, which makes information on each file system always printed on exactly one line. "column -t" makes a table from the input.

Run a script in parrallel over ssh
Runs a local script over ssh assuming ssh keys are in place. -P argument prints results to stdout. # Uses - https://code.google.com/p/parallel-ssh/

Get a funny one-liner from www.onelinerz.net
Put this command in .bashrc and every time you open a new terminal a random quote will be downloaded and printed from onelinerz.net. By altering the URL in the w3m statement you can change the output: 1 to 10 lines - http://www.onelinerz.net/random-one-liners/(number)/ 20 newest lines - http://www.onelinerz.net/latest-one-liners/ Top 10 lines - http://www.onelinerz.net/top-100-funny-one-liners/ Top 10 lines are updated daily.

revert a committed change in SVN
This command can be used to revert a particular changeset in the local copy. I find this useful because I frequently import files into the wrong directory. After the import it says "Committed revision 123" or similar. to revert this change in the working copy do: svn merge -c -123 . (don't forget the .) and then commit.

grep for minus (-) sign
Use flag "--" to stop switch parsing

Watch active calls on an Asterisk PBX
This handles when you have a single call or channel. Other commands will strip out the result if there is a single channel or call active because the output changes the noun to be singular instead of plural.

Update your journal
prerequisite: $ mkdir ~/journal

Write on the console without being registered
just use a space to prevent commands from being recorded in bash's history on most systems

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

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" }


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