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Read statement within while read loop

 
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# 1  
Old 08-05-2011
Read statement within while read loop
hi,

this is my script
Code:
#!/bin/ksh
cat temp_file.dat | while read line
do
  read test
  if [[ $test == "1" ]]; then
     break
  else echo "ERROR"
  fi
done

when i execute this code , the script does wait for the user input . it directly prints "ERROR" and terminates after the no. of times as there are lines in the file. couls anyone help?!
Last edited by pludi; 08-05-2011 at 09:05 AM..
# 2  
Old 08-05-2011
Code:
#!/bin/ksh
cat temp_file.dat | while read line
do
  read test < /dev/tty
  if [[ $test == "1" ]]; then
     break
  else echo "ERROR"
  fi
done

# 3  
Old 08-05-2011
Beware of useless use of cat
https://secure.wikimedia.org/wikiped...ess_use_of_cat

Try this and save some overhead. While not really an impact in this situation, in a bigger program it will have a bigger impact and it is just a good habit to get into.

Code:
#!/bin/ksh 
while read line 
do   
  read test < /dev/tty   
  if [[ $test == "1" ]]; then      
    break   
  else echo "ERROR"   
  fi 
done < temp_file.dat

# 4  
Old 08-12-2011
Thanks Gary and Ibrahim...
 
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