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how to determine last line in a while do loop

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# 1  
Old 06-19-2007
how to determine last line in a while do loop
Hey guy, I have a very simple question, I have the following script,

while read $test
do
echo "this is $test"
done < /testfile

What I want is instead of printing "this is $test" for each line, I want the script to print out "this is last line" for last line, how should I do it?
Last edited by fedora; 06-19-2007 at 03:41 PM..
# 2  
Old 06-19-2007
You won't know it's the last line until you fall out of the loop

do something like

Code:
LINE=

while read N
do
      if test "$LINE" != ""; then echo this is $LINE; fi
      LINE="$N"
done <file

echo this is last line $LINE

# 3  
Old 06-19-2007
Fedora,
If you just want to display the last line, here is one way:
Code:
tail -1 input_file

# 4  
Old 06-19-2007
thanks guys, i think I did not explain clearly of my question,

I have a bunch of files to process, which contain many usernames, I want every last name in every file to be treated special, something like this (I know this is not a real shell scipt):

while read name

do

if "the position of name"!="last name in the file"; then

function1

else

function2

fi

done < /tmp/filename/*
# 5  
Old 06-19-2007
Here is one way:
Code:
typeset -i mTotLines
typeset -i mCntLines=0
mTotLines=`cat input_file | wc -l`
while read mLine
do
  mCntLines=${mCntLines}+1
  if [ ${mCntLines} -eq ${mTotLines} ]; then
    echo "Last line"
  else
    echo "Not the last line"
  fi
done < input_file

# 6  
Old 06-19-2007
Quote:
Originally Posted by fedora
thanks guys, i think I did not explain clearly of my question,

I have a bunch of files to process, which contain many usernames, I want every last name in every file to be treated special, something like this (I know this is not a real shell scipt):
Code:
while read name
do 
  if "the position of name"!="last name in the file"; then
    function1
  else
    function2
  fi
done < /tmp/filename/*


Code:
prev=
while IFS= read -r line
do
   [ -n "$prev" ] && function1 "$prev"
   prev=$line
done < FILE
function2 "$prev"

# 7  
Old 06-19-2007
ah, never thought this, thank you Shell_Life!
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