Commands using perl (369)

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Rename files in batch

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Monitor all DNS queries seen by the local machine

Use a var with more text only if it exists
See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.

Get creation date of a file on ext2-3-4 fs
Return the creation date of a file on ext2, 3, 4 filesystems, because stat command won't show it. Useful on ubuntu, debian, and else

Random Number Between 1 And X
If X is 5, it will about a number between 1 and 5 inclusive. This works in bash and zsh. If you want between 0 and 4, remove the +1.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Get IP address from domain
shorter (thus better ;-)

Does a traceroute. Lookup and display the network or AS names and AS numbers.
From the man page. lft ? display the route packets take to a network host/socket using one of several layer-4 protocols and methods; optionally show heuristic network information in transitu -A Enable lookup and display of of AS (autonomous system) numbers (e.g., [1]). This option queries one of several whois servers (see options 'C' and 'r') in order to ascertain the origin ASN of the IP address in question. By default, LFT uses the pWhoIs service whose ASN data tends to be more accurate and more timely than using the RADB as it is derived from the Internet's global routing table. -N Enable lookup and display of network or AS names (e.g., [GNTY-NETBLK-4]). This option queries Prefix WhoIs, RIPE NCC, or the RADB (as requested). In the case of Prefix WhoIs or RADB, the network name is displayed. In the case of RIPE NCC, the AS name is displayed.

Do quick arithmetic on numbers from STDIN with any formatting using a perl one liner.
Good for summing the numbers embedded in text - a food journal entry for example with calories listed per food where you want the total calories. Use this to monitor and keep a total on anything that ouputs numbers.


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