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AWK Output not working with tail -f

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# 1  
Old 09-24-2009
AWK Output not working with tail -f

Hi ,

I have Continuous updating log file. I want to continuously scan that file using "tail -f " and execute a shell command like "date" command when that particular keyword is detected .

I am using awk to acheive it but not suceeded so far. However when I use "cat" instead of tail -f this statement works.. I am using ksh . can somebody tell where the problem could be.

tail -f alarms.log | awk -- '/CRITICAL_ALM/ {if ($12==8974) {print "date"}}' | sh
# 2  
Old 09-24-2009
Please post sample lines, including a sample alarm line.
Please state the largest size of the log, the largest number of records and the frequency of starting a new log.

The main issue is that the "awk" in the script pipes a number of strings containing "date" to "sh" but does not end the stream to allow "sh" to execute the commands. The approach is flawed.
# 3  
Old 09-25-2009
This should work:
tail -f alarms.log | awk '/CRITICAL_ALM/ {if ($12==8974) {system("date")}}'

# 4  
Old 09-25-2009
Viola !! Its Working

Originally Posted by jlliagre
This should work:
tail -f alarms.log | awk '/CRITICAL_ALM/ {if ($12==8974) {system("date")}}'

Hi .. Awesome , its working ...You are GREAT !!!! Many many Thanks, I am able to implement this Logic and complete my project now .. Many Many Thanks Once Again . ImageCheers

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