Like the find-src.sh script but greps the files found via find-src.sh mechanics.

grep-src.sh

#!/bin/bash                                                                                                          

usage() {
    while [ $# -gt 0 ]; do echo "$1"; shift; done
    echo "usage: $(basename $0) [options] <PATTERN> [path ...]"
    echo "options:"
    echo "  -?   This usage information screen"
    echo "  -N   Dry run, just print command"
    echo "  -t   Explicit source file extn"
    echo "  -i   Case-insensitive (egrep)"
    echo "  -L   Filenames without match (egrep)"
    echo "  -l   Filenames with match (egrep)"
    echo "  -h   No filename (egrep)"
    echo "  -n   Line number (egrep)"
    echo "  -Z   Output NULL instead of newline (egrep)"
    echo
    echo "Note: defaults to \"grep-src -t sh -t pl -t php -t py\""
    exit 1
}

GREP_OPTS=()
DRY_RUN=0
CONDS=()
while getopts ":?Nt:viLlhnZ" ARG "$@"
do
    case "${ARG}" in
        "?") usage ;;
        "N") DRY_RUN=1 ;;
        "t")
            [ ${#CONDS[@]} -gt 0 ] && CONDS+=("-o")
            CONDS+=("-name" "\"*.${OPTARG}\"")
            ;;
        "i") GREP_OPTS+=("-i") ;;
        "L") GREP_OPTS+=("-L") ;;
        "l") GREP_OPTS+=("-l") ;;
        "h") GREP_OPTS+=("-h") ;;
        "n") GREP_OPTS+=("-n") ;;
        "Z") GREP_OPTS+=("-Z") ;;
        "--")
            break
            ;;
    esac
done
shift $((OPTIND-1))

[ $# -eq 0 ] && usage "Error: PATTERN is a required argument."
PATTERN="$1"
shift

if [ ${#CONDS[@]} -eq 0 ]
then
    CONDS+=("-name" "\"*.sh\"")
    CONDS+=("-o")
    CONDS+=("-name" "\"*.pl\"")
    CONDS+=("-o")
    CONDS+=("-name" "\"*.php\"")
    CONDS+=("-o")
    CONDS+=("-name" "\"*.py\"")
fi

COMMAND=()
COMMAND+=("egrep")
for g in "${GREP_OPTS[@]}"
do
    COMMAND+=("${g}")
done
COMMAND+=("${PATTERN}")
COMMAND+=('`')
COMMAND+=("find")
COMMAND+=("$@")
for c in "${CONDS[@]}"
do
    COMMAND+=("${c}")
done
COMMAND+=('`')

if [ $DRY_RUN -eq 1 ]
then
    echo "${COMMAND[@]}"
    exit 0
fi
eval ${COMMAND[@]}
exit $?