UNIX for Dummies Questions & Answers

Hello guys,

This truly is a newbie question. I'm trying to make a loop to execute simultaneous commands indefinitely while using variable. Here is how my mess looks like (this is just an example):

Code:

#!/bin/bash
IP=`shuf -n 1 IP.txt`  # I figured this would be easier to select random lines from a file
TIMES=`shuf -n 1 TIMES.txt`

while :
do
ping -c $TIMES $IP &  # "&" to execute commands simulatenously, right?
ping -c $TIMES $IP &
ping -c $TIMES $IP &
	sleep 1
done

expected results: $IP and $TIMES should be different each time, the script should wait for each ping command to be finished (with success or not) to restart this particular ping command.

Could somebody explain to me what's wrong here?


Thank you very much

Where is your script "reading" the new IP for the while loop ? (I see not...)

I would have expected:

Code:

...
..
while read IP
do
   .
   .
#or 
while IP=`command...`
do
   .
   .

Sorry for not showing more attention, Im doing two others things at the same time + a nasty issue at work...

OK extra info: I see no update of your variable IP in your loop... So It is quite normal it shows the same...

In the stupid mind of mine, I thought that using $IP should execute `shuf -n 1 IP.txt` each time $IP is used...

So youve got the logic right now ?

Yes, the logic, thanks vbe. I've got some reading to do now

---------- Post updated at 06:40 AM ---------- Previous update was at 06:31 AM ----------

Code:

ping -c `shuf -n 1 TIMES.txt` `shuf -n 1 IP.txt`  does the trick !

Now, I need to find a way for the script to execute all commands simultaneously while at the same time waiting for each ping command to be finished to restart this particular command. I'll update my post once I get it to work.

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