Linux Cut command

Cut Command
------------

Divide a file into several parts (columns)

syntax:
cut [-b] [-c] [-f] list [-n] [-d delim] [-s] [file]

Examples:
--------

1. Let say you have a file test.txt which has colon(:) seperated data

406378:Sales:Itorre:Jan
031762:Marketing:Nasium:Jim
636496:Research:Ancholie:Mel
396082:Sales:Jucacion:Ed

If you want to print first set of data from each row, you can use cut command as follow:

cut -d":" -f1 test.txt

If you want to print just columns 1 to 6 of each line (the employee serial numbers), use the -c1-6 flag, as in this command

cut -c1-6 test.txt

Linux Tips

Repeat a command (yes 'date;sleep 5' | ksh)
Replace newline with comma (cut -d, -f1 vishnu.csv | tr '\n' ',')
Get some specific string from each line (grep "uid%3D" <fileName> |awk -F"uid%3D" ` {print $2}` | cut -d"%" -f1)
Pull first n characters of each line from a file (cut -c1-n file.txt > newfile.txt)
Count total number of lines in all specific files under a directory (find . -type f -name '*.as' -o -name '*.mxml' -o -name '*.java'| xargs cat |wc -l)
Find number of occurrences of a text in a file (grep text fileName |wc -l)
Display the top most process utilizing most CPU (top -b 1)
Show the working directory of a process ? (pwdx pid )
Display the parent/child tree of a process ? (ptree pid )
Display the no.of active established connections to localhost ? (netstat -a | grep EST)
How to create null file ? (cat /dev/null > filename1)
Display top ten largest files/directories ? (du -sk * | sort -nr | head)
Display disk usage (du -h)
How to save man pages to a file ? (man | col -b > filename )
Display the files in the directory by file size ? (ls -ltr | sort -nr -k 5)
Display the processes, which are running under yourusername ( ps -aef | grep username)
Display the all files recursively with path under current directory ? ( find . -depth -print)
Display the Disk Usage of file sizes under each directory in currentDirectory ? (du -k . | sort -nr)
List the files in current directory sorted by size ? (ls -l | grep ^- | sort -nr)

Soalris: Kill a process which is using a particular port number

Today i came across a problem in solaris. The problem was that while starting my application server, it was throwing an error "Address already in use".

My app server is a java process and there are many other java process which are running on my zone. But the issue is, how may i know that which java process is using that particular port?

I followed following steps:
1. List all the java process running on my zone ( ps -eaf |grep vagrawal| grep java )
2. Go through each java process and check if it using that particular port ( pfiles $pid|grep 1182 )
(here $pid is the process id of the java process and 1182 is the port number of which i am looking for)


Above method works fine but it is bit a long process, as i have to run step 2 for all java processes, so i ran a folowing command on my console:

for i in `ps -e|awk '{print $1}'`; do echo $i; pfiles $i 2>/dev/null | grep 'port: 1188'; done

Above command/script will list out all the process ID and will tell if any process is using port 1188

Now i have process ID of the process which is occupying my port, and i can kill that by kill -9 pid