var from getline does not change

[suhaimi]

Hi,
Why my variable "tt" does not change eventhough I continuously add couple of lines in to test.data file????

tail -f test.data|nawk '{"ls -ltr test.data"|getline tt;print tt;}'
-rw-r--r-- 1 oracle dba 2083 Jul 22 15:10 test.data
-rw-r--r-- 1 oracle dba 2083 Jul 22 15:10 test.data
-rw-r--r-- 1 oracle dba 2083 Jul 22 15:10 test.data

Rgds,
Suhaimi

 

[Salem]

Probably because awk isn't restarting the internal pipe you've set up

Try

tail -f test.data | 
  nawk '{"ls -ltr test.data"|getline tt;
         close("ls -ltr test.data");
         print tt;}'

 

[suhaimi]

Thanks alot salem. It helps....