exclude header lines

exclude_header.sh

#!/bin/bash

usage()
{
    echo "usage: $0 <folder> <matching_string> <n>"
    echo "  extract all first n header files from a file which is matching matching_string"
    echo "  ex) $0 . 'matching string' 15"
}

if [ $# -ne 3 ];then
    usage
fi

FOLDER=$1
MSTR=$2
EXLINES=$3

for f in `find $FOLDER -type f`;do
    grep "$MSTR" $f 2>/dev/null >/dev/null
    if [ $? -ne 0 ];then
        continue
    fi
    tail -n+$EXLINES $f > $f.tmp
    mv -f $f.tmp $f
    echo "Extract first $EXLINES lines from <$f>"
done