Commands by tokland (1)

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Compare a remote dir with a local dir
You can compare directories on two different remote hosts as well: $ diff -y

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

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 top ten files/directories sorted by size

sort lines by length
making it "sound" more "natural" language like -- additionally sorting the longest words alphabetically: this approach is using: * to get at all lines of input * post-"for" structure * short-circuit-or in sort: if the lengths are the same, then sort alphabetically otherwise don't even evaluate the right hand side of the or * -C sets all input and ouput channels to utf8

find text in a file
this will find text in the directory you specify and give you line where it appears.

Remove Backup Files
Remove all text backup files.

Backup all MySQL Databases to individual files
No need to loop when we have `xargs`. The sed command filters out the first line of `show databases` output, which is always "Database".

Ctrl+S Ctrl+Q terminal output lock and unlock
These are simple shortcuts to pause and continue terminal output, works in most terminals and screen multiplexers like screen. You can use it to catch something if things change too fast, and scroll with Shift + PgUp PgDown. On linux console ScrollLock can also be used.

back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

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