Commands by drwlrsn (1)

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Does a full update and cleaning in one line

List upcoming events on google calendar
Requires googlecl (http://code.google.com/p/googlecl/) Even better when you wrap this in a script and allow the --date=STRING to be $1. Then you can type: whatson "next Thursday" The date string for UNIX date is very flexible. You can also add --cal "[regex]" to the end for multiple calendars.

Check your spelling
For when you need a quick spell check.

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

concatenate compressed and uncompressed logs
I use zgrep because it also parses non gzip files. With ls -tr, we parse logs in time order. Greping the empty string just concatenates all logs, but you can also grep an IP, an URL...

When feeling down, this command helps
$ sudo apt-get install sl $ man sl

Display last exit status of a command
The variable ? contain the last exit status of a command, it can be printed for troubleshooting purpose.

Grep without having it show its own process in the results
The trick here is to use the brackets [ ] around any one of the characters of the grep string. This uses the fact that [?] is a character class of one letter and will be removed when parsed by the shell. This is useful when you want to parse the output of grep or use the return value in an if-statement without having its own process causing it to erroneously return TRUE.

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 all file-types (case-insensitive extensions) including subdirectories


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