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Monitor Applications application that are connected/new connections

Terminal - Monitor Applications application that are connected/new connections
while true; do netstat -p |grep "tcp"|grep --color=always "/[a-z]*";sleep 1;done
2009-07-16 04:52:49
User: buffer
Functions: grep netstat
-4
Monitor Applications application that are connected/new connections

The -p parameter tell the netstat to display the PID and name of the program to which each socket belongs or in digestible terms list the program using the net.Hope you know what pipe symbol means!

Presently we wish to only moniter tcp connections so we ask grep to scan for string tcp, now from the op of grep tcp we further scan for regular expression /[a-z]*.

Wonder what that means ?

If we look at the op of netstat -p we can see that the name of the application is preceded by a / ( try netstat -p ) so,now i assume application name contains only characters a to z (usually this is the case) hope now it makes some sense.Regular expression /[a-z]* means to scan a string that start with a / and contains zero or more characters from the range a-z !!. Foof .. is t

Alternatives

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Terminal - Alternatives

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What others think

use netstat -tp and you can drop the |grep "tcp".

oh and this is not a command to use on a box running bittorrent. the hostname lookups for a few hundred hosts would cause the netstat part to take far too long to be useful.

Comment by TheMightyBuzzard 319 weeks and 3 days ago

remove the loop and use (in addition to themightybuzzard's suggestion):

watch -n 1 "command"
Comment by linuxrawkstar 319 weeks and 3 days ago

use

$ while sleep 1; do ..; done

and

$ netstat -pt

Comment by ioggstream 319 weeks and 3 days ago

watch -n1 'netstat -anpt' is a way shorter, doesn't try to resolve hostnames

Comment by unixmonkey4704 319 weeks and 2 days ago

Your point of view

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