Decrease buffer size

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1

Hi,
I am using the below command to get the output in a file called "Logs.txt"

 tail -f filename | egrep -i "cpu | hung " >> Logs.txt

The problem is the Logs.txt file gets updated only after the buffer is 8Kb, but i want to update the file immediately and not wait for the buffer to get 8kb.
Is there a way to decrease the buffer size.

Thanks

2

If your version of egrep supports it, try --line-buffered

3

Is there any other option --line-buffered is not supported.

4

What is your system?

5

SunOS 5.10

6

Is there any other way to decrease the buffer size

8

The problem isn't the buffer size per se, but the fact that it's buffering at all... Maybe try an alternate command:

tail -f filename | nawk '/[cC][pP][uU] | [hH][uU][nN][gG]/'
9

Or try shell:

tail -f filename | 
while IFS= read -r line; do 
  case $line in  
    (*"cpu "*|*" hung "*) printf "%s\n" "$line"
  esac
done >> Logs.txt

(On Solaris, use bash, ksh, or /usr/xpg4/bin/sh, but do not use /bin/sh)
This is not case insensitive. Does it need to be case insensitive too?

10

Thanks :b:
Case insensitive is not needed.