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How to Read the entire file using while loop

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# 1  
Old 05-22-2009
How to Read the entire file using while loop
Guys,
I am trying to read the whole file using while loop but when i run the ssh part of the script it reads only the first line and exit after that.

There are in total 134 lines in the file, but when the output is redirected, it does only for one line and comes to command prompt.
pls help..

Code:
FILENAME=/tmp/Parser_list_beauty
while read line
do
PARSER_NAME=`echo $line | awk ' { print $1; } '`
HOST_NAME=`echo $line | awk ' { print $2; } '`
echo "-------------------------------------------------------" 
echo "Extracting information for $PARSER_NAME on $HOST_NAME" 
echo " " 
ssh $HOST_NAME grep STANDBY /ilx/gtp/pkg/$PARSER_NAME/log/$PARSER_NAME.log | tail -2 
echo "-------------------------------------------------------" 
done < $FILENAME >> /tmp/parser_extract.txt 
 
The o/p file is
cat /tmp/parser_extract.txt
-------------------------------------------------------
Extracting information for ASXITSparser on spoonl1
0522 085504 (gtp) STATUS: Operational timer signaling process from UP to STANDBY.
0522 085506 (gtp) STATUS: Operational timer signaled process to STANDBY; in STANDBY state, ignoring signal.
-------------------------------------------------------

While it should reflect all the 134 lines output. pls advise.
Last edited by sdosanjh; 05-22-2009 at 07:13 AM..
# 2  
Old 05-22-2009
To read a file line by line I should use:
Code:
cat $FILENAME | while read line; do 
   PARSER_NAME=`echo $line | awk ' { print $1; } '`
   HOST_NAME=`echo $line | awk ' { print $2; } '`
   #[...]
done

Regards,

Albert.
# 3  
Old 05-22-2009
Remove this part of the ssh command:

Code:
| tail -2

Regards
# 4  
Old 05-22-2009
Hi Franklin and Albert,

Thanks for the reply, but still hard luck. and if i remove tail -2 ; then it may produce lot of o/p since i am greeping the expression from the log files.

Any other way??? pls suggest.
Actually when i run the code without the following line, it works well but i don't know how to handle this ssh part now...

ssh $HOST_NAME grep STANDBY /ilx/gtp/pkg/$PARSER_NAME/log/$PARSER_NAME.log | tail -2
# 5  
Old 05-22-2009
Quote:
Originally Posted by AlbertGM
To read a file line by line I should use:
Code:
cat $FILENAME | while read line; do 
   PARSER_NAME=`echo $line | awk ' { print $1; } '`
   HOST_NAME=`echo $line | awk ' { print $2; } '`
   #[...]
done

Regards,

Albert.
no need to cat. Also , if using awk, no need to use while read loop
Code:
awk '{
   parsername=$1
   hostname=$2
   #some other code
}' $filename

# 6  
Old 05-22-2009
Hard luck

> awk '{
>> PARSER_NAME=$1
>> HOST_NAME=$2
>> ssh -X $HOST_NAME grep STANDBY /ilx/gtp/pkg/$PARSER_NAME/log/$PARSER_NAME.log >> /tmp/parser_extract.txt
>> echo "--------------------------------------------------------------------"
>> echo " "
>> }' $FILENAME
awk: syntax error near line 4
awk: illegal statement near line 4
# 7  
Old 05-22-2009
my issue is ... while loop reads first line only from the input file and then redirects the o/p to output file and then returns to command prompt ignoring the other lines of the file.
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