Commands by scanepa (2)

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Insert commas to make reading numbers easier in the output of ls
This modifies the output of ls so that the file size has commas every three digits. It makes room for the commas by destructively eating any characters to the left of the size, which is probably okay since that's just the "group".   Note that I did not write this, I merely cleaned it up and shortened it with extended regular expressions. The original shell script, entitled "sl", came with this description:    : '  : For tired eyes (sigh), do an ls -lF plus whatever other flags you give  : but expand the file size with commas every 3 digits. Really helps me  : distinguish megabytes from hundreds of kbytes...  :  : Corey Satten, corey@cac.washington.edu, 11/8/89  : '   Of course, some may suggest that fancy new "human friendly" options, like "ls -Shrl", have made Corey's script obsolete. They are probably right. Yet, at times, still I find it handy. The new-fangled "human-readable" numbers can be annoying when I have to glance at the letter at the end to figure out what order of magnitude is even being talked about. (There's a big difference between 386M and 386P!). But with this nifty script, the number itself acts like a histogram, a quick visual indicator of "bigness" for tired eyes. :-)

Run a bash script in debug mode, show output and save it on a file
Sends both stdout and stderr to the pipe which captures the data in the file 'out.test' and sends to stdout of tee (likely /dev/tty unless redirected). Works on Bourne, Korn and Bash shells.

Get a process's pid by supplying its name

Check variable has been set

Command to keep an SSH connection open
This runs the uptime command every 30 seconds to avoid an SSH connection dropping due to inactivity. Granted there are better ways of solving this problem but this is sometimes the right tool for the job.

Display 6 largest installed RPMs sorted by size (descending)
Low on disk space? Check the largest installed RPMs for delete canditates.

Check if a domain is available for purchase
A quick alias to check if a domain is already registered or if it's available for purchase.

Get pages number of the pdf file

purge all packages marked with 'rc'
After you install/remove lots of packages, there are many packages marked with 'rc'. This script help you to purge these packages, it will save some spaces from your disk.

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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