While loop help bash

Question

I have a while loop that tries to curl a weblink for a term.. I need to add an "or" in to it, so I can count up for a time period, so that if if page never comes up, it just doesn't stall the script indefinitely. Here is what I have, that isn't working.

count=0
while [ $count -lt 5 -o `curl -silent -m 2 10.10.10.10:7001 | grep myterm | wc -l` -lt 1 ]; do 
echo "Waiting for it to start" 
count=$(($count + 1))
sleep 5
done
echo "started"

I know my curl works and returns 1 when the page is up, and the count part works fine, if it loops through 5 times, it ends the while loop and says started(not how I am leaving it, just an example). Yet the first time it runs, it should see that my curl = 1, which is not less than 1, and end the while loop.. What am I doing wrong??

EDIT: To explain why I am doing it this way, so someone can explain why it is bad practice/what to do instead.

I am starting a jboss service. This service can take anywhere from 3 to 6 minutes to start. So I need to do 2 things. Check for the status page to come up(best way to tell when it has successfully started), and, if it takes more than 8 minutes to come up, to stop checking so that it can move on to the next service. Thoughts?

You're doing a lot of things "wrong" (understand "not very good practice"). — gniourf_gniourf
– gniourf_gniourf, Commented Oct 30, 2013 at 17:07
Are you looking for a timeout? stackoverflow.com/questions/687948/… — freitass
– freitass, Commented Oct 30, 2013 at 17:09
Did you understand that the condition in your while is an or condition? — gniourf_gniourf
– gniourf_gniourf, Commented Oct 30, 2013 at 17:12
Yes, I need or. I need it to finish the loop if it is able to curl the page and the value returned to be greater than 0 OR if the count reaches 5. I need it so that if either of those conditions is true, the while loop ends. — cashman04
– cashman04, Commented Oct 30, 2013 at 17:15
Note that -silent is 4 different curl options, not just requesting silence (which is -s by itself, or --silent with two dashes). The other options you're inadvertently passing are -i, which includes the response headers in the output; -l, which is for getting a directory listing out of an ftp:// URL and makes no sense here; and -e, which specifies a Referer header - in this case, "nt". — Mark Reed
– Mark Reed, Commented Oct 30, 2013 at 17:21

remram · Accepted Answer · 2013-10-30 17:16:16Z

1

What you're trying to do is keep trying while you haven't yet tried 5 times and it fails. But you didn't write that.

count=0
nb=0
while [ $count -lt 5 ]; do 
  nb=$(curl -silent -m 2 10.10.10.10:7001 | grep myterm | wc -l)
  if [ $nb -ge 1 ]; then
    echo "Started"
    exit 0
  fi
  echo "Waiting for it to start..." 
  count=$(($count + 1))
  sleep 5
done
echo "Didn't start after $count tries"
exit 1

answered Oct 30, 2013 at 17:16

remram

5,2771 gold badge32 silver badges45 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

cashman04 Over a year ago

This worked for me. In the end I just changed my code from -o to -a and it works fine. I guess I was misunderstanding my own conditions. I get it now why and works. Thanks very much.

Collectives™ on Stack Overflow

While loop help bash

1 Answer 1

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related