Commands tagged awk (348)

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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"

Rename file to same name plus datestamp of last modification.
Note that the -i will not help in a script. Proper error checking is required.

Read null character seperated fields from a file
Handle any bad named file which contains ",',\n,\b,\t,` etc Store the file name as null character separated list $find . -print0 >name.lst and retrieve it using $read -r -d "" Eg: $find . -print0 >name.lst; $cat name.lst| while IFS="" read -r -d "" file; $do $ls -l "$file"; $done

Get the IP address of a machine. Just the IP, no junk.

Convert YAML to JSON
Converts YAML file to JSON. Note that you'll need to install PyYAML. Also some YAML data types (like dates) are not supported by JSON).

find all active IP addresses in a network

mtr, better than traceroute and ping combined
mtr combines the functionality of the traceroute and ping programs in a single network diagnostic tool. As mtr starts, it investigates the network connection between the host mtr runs on and HOSTNAME. by sending packets with purposly low TTLs. It continues to send packets with low TTL, noting the response time of the intervening routers. This allows mtr to print the response percentage and response times of the internet route to HOSTNAME. A sudden increase in packetloss or response time is often an indication of a bad (or simply over‐loaded) link.

pngcrush all .png files in the directory
Nothing too magical here, just uses pngcrush to losslessly compress all your pngs!

Remove newlines from output
Remove newlines from output. One character shorter than awk /./ filename and doesn't use a superfluous cat. To be fair though, I'm pretty sure fraktil was thinking being able to nuke newlines from any command is much more useful than just from one file.

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"


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