Commands by snahor (1)

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Cancel all aptitude scheduled actions
Very handy if you have done a package selection mistake in aptitude. Note that it's better to do a Ctrl+U (undo) in aptitude if possible, because the keep-all will clear some package states (like the 'hold' state).

Convert unix timestamp to date
The "-d" option for gnu's "date" command can calculate positive or negative offset from any time, including "now". You can even specify a source timezone (the output timezone can be set with the TZ environment variable). Useful! Fun! Not very well documented!

Multiple SSH Tunnels
Thankfully, the ssh command allows you to specify multiple tunnels through the same server in one command. Remeber if you want a priviliged port on your machine, you must use root or sudo account.

count of down available ips
avoid wc overload ;)

Update zone file Serial numbers
Will edit *.db files in the same directory with todays date. Useful for doing a mass update to domains on a nameserver, adding spf records, etc. Looks for a string starting with 200 or 201 followed by 7 numbers, and replaces with todays date. This won't overwrite Ip's but i would still do some double checking after running this. Make sure your server's date is correct, otherwise insert your own serial number. $rndc reload should usually follow this command.

Find files changed between dates defined by ctime of two files specified by name
This command finds all the files whose status has changed between the ctime of the older and newer . Very useful if you can see from an ls listing a block of consecutive files you want to move or delete, but can't figure out exactly the time range by date.

Find all dot files and directories

Complete TCP Handshake on a given host-port
Try to perform a fully TCP 3 way handshake on for a given host-port with a timeout of 1s.

list files recursively by size

Clear filesystem memory cache


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