#!/bin/bash
#grepstatus.sh
#Usage: ./grepstatus.sh "<grep options>" "<filename>" "pipe to commands"
#Example:  ./grepstatus.sh "a" /usr/share/dict/words "sed 's/^[0-9]\+://g' |sort |uniq >/tmp/f.txt"
#       "-n" flag is already passed by default which means your output will have line numbers returned at the end to get rid of this
#       use sed "s/^[0-9]\+://g"
#-cripy

        if [ $# -lt 2 ]; then
                printf "Usage: ./grepstatus.sh '<grep options>' '<filename>' 'pipe to commands'\n"
                printf "Example: ./grepstatus.sh 'a' /usr/share/dict/words 'sed \"s/^[0-9]\+://g\" |sort |uniq >/tmp/f.txt'\n"
                printf "\t\t-n flag is already passed by default which means your output will have line numbers returned.\n"
                printf "\t\tTo get rid of this pipe sed \"s/^[0-9]\+://g\"\n"
                exit
        fi;
        PIPE_CMD=""
        if [ "$3" != "" ]; then PIPE_CMD="| $3"; fi;
        LINE_COUNT=`wc -l $2|awk '{print $1}'`
        CMD="grep -n $1 $2 $PIPE_CMD &"
        eval $CMD

        GREP_PID=`ps aux|grep "0:0[0-9] grep"|grep 0:0[0-9] |grep -v -e 'grep 0:0'|awk '{print $2}'`
        CUR_LINE=0;
        P=`ps aux |awk '{print $2}' |grep $GREP_PID`

        while [ "$P" != "" ]; do
                CUR_LINE=`strace -s 40 -e trace=write -p $GREP_PID 2>&1|head -2|grep -oe "\n[0-9]*:" |sed "s/[n:]//g" |tail -1|tr "\n" ' '`
                tput el
                printf "\rline: $CUR_LINE of: $LINE_COUNT"
                printf "| %s %% complete" `python -c "print repr($CUR_LINE*100/$LINE_COUNT.0)"` 
                P=`ps aux |awk '{print $2}' |grep $GREP_PID`
        done;
        printf "\n"