Write $line number into textfile and read from line number

Shell Programming and Scripting
1

Hello everyone,

I don't really know anything about scripting, but I have to manage to make this script, out of necessity.

#!/bin/bash
while read -r line; do #I'm reading from a big wordlist
instructions using $line
done

Is there a way to automatically write the $line number the script is at into a separate textfile and read from the line number so that I won't have to start everything from scratch in case I have to stop the script?

Thank you very much !

2 
#!/bin/bash
CPT=0
while read -r LINE #I'm reading from a big wordlist
do
       CPT=$((CPT+1))
       instructions using $LINE
       echo "CPT="$CPT > ~/interrupted_at_line.log #will be in your $HOME
done
1 Like
3

Thank you. It's working well: it tells me precisely at which line the script stopped.
But how do you start reading from this very line though?

4

I think you will have to show what you are reading... Is it a file?
what format?

5

It's a wordlist. utf8.
One word per line.

---------- Post updated at 11:32 AM ---------- Previous update was at 11:23 AM ----------

Somebody helped me out (Santhosh). I'm going to copy paste the code here just in case someone needs it in the future.

#!/bin/bash

TMP_FILE="/tmp/currentLineNumber"                         # a constant

current_line_count=0                                      # track the current line number

processed_lines_count=0

# Verify if we have already processed some stuff.
if [ -r "${TMP_FILE}" ]; then
  processed_lines_count=$(cat ${TMP_FILE})
fi

while read -r line; do                                    # I 'm reading from a big wordlist

    # Skip processing till we reach the line that needs to be processed.

    if [ $current_line_count -le $processed_lines_count ]; then

      # do nothing as this line has already been processed
      current_line_count=$((current_line_count+1))        # increment the counter
      continue

    fi

    current_line_count=$((current_line_count+1))
    echo $current_line_count > ${TMP_FILE}                # cache the line number

    # perform your operations
    command1 using $line
    command2 using $line

done