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Shell programming

Hello
I want to read one file line by line by my shell script
(Just like reading file in C by fopen and then getch/gets).
After reading it i want to delete that line.
How I can achive this and using which utility?

sac

Doesn't make too much sense to me ... what's the background of this?
You could just read all lines and then delete the whole file? :)

Cheers,
Tink

here's some concepts

Code:

cat file > tmp

IFS=$'\n'

for a in $(<tmp); do

    # remove the line

    sed -i -n 1\!p file

    # OR sed -i -n /"$a"/\!p file 

done

I understand that you want to process each line somehow and have the line removed when you're done with it?
So,

Code:

#! /bin/bash



FILENAME=your_file



while [[ -s "$FILENAME" ]]

do

  read < "$FILENAME"

  sed -i '1d' "$FILENAME"

  echo "$REPLY processed and deleted."

done

To me, this only seems to make sense if other processes may append lines to the file, and in that case you'll need some file locking (in both the reading and writing processes). Have a look at

Code:

#! /bin/bash



FILENAME=your_file



while [[ -s "$FILENAME" ]]

do

  LINE=$( flock "$FILENAME" \

          bash -c "read <'$FILENAME';\

                  sed -i 1d '$FILENAME';\

                  echo \"\$REPLY\"" )

  echo "$LINE processed and deleted."

done

This can be as simple as:

Code:

while read line <file; do process $line; sed -i '1 d' file; done

Yves.