Just finished my first script. Need a bit of help formatting it.

panchosansa · 10-09-2006, 10:38 AM

Hi everyone,

It's a pleasure for me to join your community.
I am still a "freshman" in Linux and in bash scripting, but I am glad to say that with a bit of help I managed to complete my first script. But much more important is the fact that I am getting increasingly enthusiastic and hooked to this great OS and the many unique possibilities that scripting presents...
And here is the final product of many hours of hard work

Code:

#!/bin/bash
echo
echo "This script will find all the open ports on a computer."
echo "It will also show the process that has opened each one and the number of files opened per process."
echo
echo

showProcesses()
{	
   lsof -i | uniq -f 7 > table.list
   cat table.list | awk 'NR>1{print "Process name\t"$1"\t\t\ton port\t\t"$8}'
}

showNumberOfFiles()
{
	cat table.list | awk 'NR>1{print $2}' > PID.list
	while read pid; do
	lsof -p $pid | wc -l | awk '{print "\t\t\tNumber of files opened\t"$1}'
	done < PID.list
}

showProcesses > file1.list

showNumberOfFiles > file2.list

paste file1.list file2.list

echo

It's a fairly simple one and what I want to do with it now is to format it like a table. I used the paste command and some tabs to try and allign the data so that it is legible but coudldn't do it. Does anyone have an idea how I can accomplish this?

Kindest regards,
Valentin

unSpawn · 10-10-2006, 05:53 AM

Hello and welcome to LQ. Hope you like it here.

Pipe the output through "column -t":

Code:

output() { lsof -w -n -i | uniq -f 7; }
output | awk 'NR>1{print "Process name\t"$1"\t\t\ton port\t\t"$8}' | column -t
output | awk 'NR>1{print $2}' | while read pid; do 
 lsof -w -n -p $pid | wc -l | awk '{print "\t\t\tNumber of files opened\t"$1}'
done | column -t

BTW, as you see you don't have to use temporary files. If you do it's best to use "mktemp" for that and have a portion of the name be the same as the script you're running so you can spot them if they don't get deleted. Also note the output function (saves typing), the switches for lsof (just my best practice to discard warnings and speedup by discarding resolving) and the number of open files (true in the sense everything is a file but those are not all real files).

panchosansa · 10-10-2006, 06:07 AM

Thanks very much, unSpawn. I enjoy my time here and I am sure I would be a regular on this forum because I want to develop my scripting skills. I've found your remarks very useful and will bear them in mind for future reference.

chrism01 · 10-10-2006, 08:31 PM

you may also want to look at printf() http://www.tldp.org/LDP/abs/html/internal.html#EX47
based on C fn of same name.