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show the real times iso of epochs for a given column
When you have one of those (log)files that only has epoch for time (since no one will ever look at them as a date) this is a way to get the human readable date/time and do further inspection. Mostly perl-fu :-/

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"

Show which programs are listening on TCP and UDP ports
-p Tell me the name of the program and it's PID -l that is listening -u on a UDP port. -n Give me numeric IP addresses (don't resolve them) -t oh, also TCP ports

Find status of all symlinks
The symlinks command can show status of all symbolic links, including which links are dangling, which symlinks point to files on other file systems, which symlinks use ../ more than necessary, which symlinks are messy (e.g. having too many slashes or dots), etc. Other useful things it can do include removing all dangling links (-d) and converting absolute links to relative links (-c). The path given must be an absolute path (which is why I used $(pwd) in the example command).

Create a zip file ignoring .svn files

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Nicely display permissions in octal format with filename
Since the original command (#1873) didn't work on FreeBSD whose stat lacks the "-c" switch, I wrote an alternative that does. This command shows also the fourth digit of octal format permissions which yields the sticky bit information.

Random numbers with Ruby
There's been a few times I've needed to create random numbers. Although I've done so in PERL, I've found Ruby is actually faster. This script generates 20 random "10" digit number NOT A RANDOM NUMBER. Replace 20 (1..20) with the amount of random numbers you need generated

Protect against buffer overflow
This command solve the problem ping: sendmsg: No buffer space available to.

for all who don't have the watch command


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