[redhead]

Something like this:

#!/bin/sh                                                                       

if [ -z $1 ]; then
    echo "Usage: $0 <file> <n>"
    exit
fi
if [ -z $2 ]; then
    echo "Usage: $0 <file> <n>"
    exit
fi
if [ ! -f $1 ]; then
    echo "File: $1 isn't a file"
    exit
fi
for n in `grep -n $ $1 | awk -F ':' '{print $1}'`; do
    LINE=`head -$n $1|tail -1`
    # fetch the first n chars from line                                         
    CHARS=`echo $LINE | cut -c 0-$2`
    # do whatever with CHARS                                                    
    echo $CHARS
done

Remember you can form your echo statement any which way you want it to be displayed, and you can use awk/cut to pick anything out of your $LINE