shell脚本---统计代码行数的工具

#!/bin/bash
#changed ws for counting the number of all the source code;
# example ./countLinesNumber.sh .

# usage info;
USAGE="Usage:\\t./countLinesNumber.sh .\\n"
# help info;
HELP="You can count the number of lines of the specified directory by this script\\n${USAGE}"
# the tmp file to save the number of lines;
COUNT_TMP_FILE=./count
# show usage when you use this script with some incorrect way;
show_usage(){
    echo -ne ${HELP}
}

# function to count lines of all your source code tree;
count_lines(){
  rm -f ${COUNT_TMP_FILE}
  touch ${COUNT_TMP_FILE}
    # excluding the error;
    if [ $# -lt 1 ]
    then
        echo "Usage: count_lines $1"
        return 1
    fi
    # start to count the number of lines;
    _DIR=$1
    echo "Start to count the number of lines in current directory ${_DIR}"
    find ${_DIR} -regex ".*\.java$\|.*\.c$\|.*\.cpp$" | \
    while read LINE
    do
        NUMLINES=`cat ${LINE} | wc -l`
        echo ${LINE}:${NUMLINES}
        NUM=`expr ${NUM} + ${NUMLINES}`
        echo ${NUM} > ${COUNT_TMP_FILE}
    done
    echo "The number of all the lines are:"
    cat ${COUNT_TMP_FILE}
    rm -f ${COUNT_TMP_FILE}
    echo "Counting Finished"
}

# main;
main(){
    if [ ! $# = 1 ]
    then
        # show help about this script;
        show_usage
        exit 1
    else
        # start to count lines;
        count_lines $1
    fi
}

# call main;
main $1