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Top Forums Shell Programming and Scripting Bash not equal string comparison Post 302920444 by cokedude on Thursday 9th of October 2014 12:04:49 PM
Old 10-09-2014
Quote:
Originally Posted by RavinderSingh13
Hi cokedude,
Could you please try following.

Code:
while [[ "$(ipcs | awk '{print $2}')" !~ "Semaphore" ]]; do
    echo "$(ipcs | awk '{print $2}')" 
done 
echo 
exit 0

Thanks,
R. Singh
This won't work Smilie.

Code:
$ bash ./whilee1
./whilee1: line 2: conditional binary operator expected
./whilee1: line 2: syntax error near `!~'
./whilee1: line 2: `while [[ "$(ipcs | awk '{print $2}')" !~ "Semaphore" ]]; do'

Quote:
Originally Posted by Akshay Hegde
For me what he tried looks right, but unfortunately he is comparing contents are not equal to a fixed string, so caught inside infinite loop.

---------- Post updated at 09:06 PM ---------- Previous update was at 09:04 PM ----------

Something like this should work I guess

Code:
#!/bin/bash


while [[ "$(ipcs | awk '{print $2}')" != *"Semaphore"* ]]; do
    echo "$(ipcs | awk '{print $2}')"

done
       
echo 
exit 0

I am bit confused with the contents



I tested like this, as soon as count reaches 500 it creates file and breaks while loop

Code:
#!/bin/bash

i=0
while [[ "$( ls )" != *"akshay"* ]]; do
    echo $i
    [ $i -eq 500 ] && touch unix.com_akshay_unix.com
i=$((i+1))
done

echo "released"

Is there a trick to get this to work?

Code:
$ while [[ "$(ipcs | awk '{print $2}')" != *"Semaphore"* ]]; do
>     echo "$(ipcs | awk '{print $2}')"
> 
> done


$ bash ./whilee1

 

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