Commands by bkmeneguello (2)

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Watch several log files in a single window
It works like a "tail -f" on several files. Use the number keys 0-9 to set a baseline in the numbered window. Pressing "b" let you scroll back in one of the windows.

Generic shell function for modifying files in-place
Some commands (such as sed and perl) have options to support in-place editing of files, but many commands do not. This shell function enables any command to change files in place. See the sample output for many examples. The function uses plain sh syntax and works with any POSIX shell or derivative, including zsh and bash.

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

Recording the desktop and an application audio source for webcast
You will have to use the sound preferences (record) to choose the audio source and set it to internal.

zsh only: access a file when you don't know the path, if it is in PATH
Say you want to execute 'file' on the command 'top' (to determine what type of file it is); but you don't know where 'top' resides: preface the argument with = and zsh will implicitly prepend the path.

Sort output by column
(separator = $IFS)

Convert a flv video file to avi using mencoder

run command on a group of nodes in parallel redirecting outputs
Do the same as pssh, just in shell syntax. Put your hosts in hostlist, one per line. Command outputs are gathered in output and error directories.

Get the serial numbers from HP RAID
This dumps serial numbers of all the drives but HP warranty check does not say they are valid ...

Quick screenshot
Requires ImageMagick. Takes a screenshot 5 seconds after it's run and saves it as desktop_screenshot.jpg Particularly handy when made into a menu option or button.


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