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While read line only reads first line in HP-UX B.11.11 system

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# 8  
Old 10-09-2014
Hi MadeInGermany,

Your suggestion worked for me!
Thanks a lot for your help.
Just a question, what is the difference between below two ways of handling loops
Code:
$CAT $TMP_FILE1 |while read sid
do
..
done

Code:
while read sid <&3 # 
do
 ...
done 3< $TMP_FILE1

is the later one is more accurate?
# 9  
Old 10-09-2014
Quote:
Originally Posted by veeresh_15
Hi MadeInGermany,

Your suggestion worked for me!
Thanks a lot for your help.
Just a question, what is the difference between below two ways of handling loops
Code:
$CAT $TMP_FILE1 |while read sid
do
..
done

Code:
while read sid <&3 # 
do
 ...
done 3< $TMP_FILE1

is the later one is more accurate?
It's not a question of "accurate", the computer does exactly what you tell it to with 100% precision.

The point is avoiding file descriptor #1, because something inside your loop "eats" it, ending the loop early.

Code:
while read LINE
do
        cat # This also reads from 'inputfile', so this loop will only run once!
done < inputfile

while read sid <&3 # 
do
        cat # It doesn't read from 'inputfile' since that's not standard input here.
done 3< inputfile
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