reading from within the loop --std i/p problem


 
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# 1  
Old 07-11-2008
reading from within the loop --std i/p problem

i have a teat file having data like

one 12/3
two 23/09
three 12/12

now from another script i want to read one line at a time ,cut field one and two in two separate variable ,compare field1 with another variable [ which is already defined ]
but outside the loop .If i found a match i want to take from user the value of
field 1 and field2 [using read ]

Now the problem is as i am reading the file like

cat File | while read LIne
do
.....
.......
done


inside the loop i cant get the std i/p free .

i mean the
read VAR line is skipping

can any one tell me how can i read from within the loop
# 2  
Old 07-11-2008
I don't know what kind of problems you have but try this:

Code:
while read line
do
  echo "$line"
  # do something else with "$line"
done < file

Regards
# 3  
Old 07-11-2008
As Franklin52 implied, your requirements aren't very clear... but I suspect you're asking how to read from standard input (as in prompting the user) when it is already being used by the surrounding while loop. You can do that by duplicating the standard input file descriptor before starting the loop, and reading specifically from the duplicated descriptor when you need to access standard input again, e.g.:

Code:
#!/usr/bin/ksh

exec 3<&0

print 'one
two
three' | while read line
do
        echo $line
        print -n "more input stephanie: "
        read -u3 input
        print "input was: $input"
done

exec 3<&-

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