25 May 2013
改进的 rm

我用 u 盘在多台电脑之间同步资料 (因为有些电脑无法上网)，然后在某台能上网的电脑上，插入 u 盘时，每隔一段时间进行一次 rsync，将 u 盘上的内容同步到 Dropbox 文件夹。日子久了，发现 Dropbox 里有很多不需要的临时文件，比如 .xxx.swp、xxx.o、a.out、xxx.ncb、xxx.txt~，散布在各个地方，想一次性删除这些文件，又担心误删，于是写了一个脚本来做这件事情，我取名为 brm，即 baurine rm 的缩写，哈哈！

代码如下：

#!/bin/sh

# name: brm
# author: baurine
# date: 2013/05/24

# if you need to delete many files, and you are afraid to make mistake,
# you can try this.

# step 1, you can use command "brm [path] express" to find out files 
# that need to delete, the result will output to console and file named
# Brmfiles under current path. 
# in internal, the script use "find path -name express" command to 
# search files.

# step 2, you can use "vim Brmfiles" or other editors to edit Brmfiles,
# check whether there are files that don't need to delete, if then 
# remove it from Brmfiles.

# step 3, now use "brm -d" to delete files. brm use "rm -f" command to 
# delete all files in Brmfiles, then rename Brmfiles to Brmfiles_done.

# use like this:
# brm *.swp
# brm /root/mywork *.swp
# brm -d [Brmfiles]

def_out=Brmfiles

function usage() {
    echo "Usage:"
    echo "  brm [path] express"
    echo "  brm -d [Brmfiles]"
}

function find_files() {
    # find ./ -name *.swp
    # find /root/mywork -name *.swp
    files_found=$(find $1 -name $2)

    if [ -z $files_found ]; then
        echo "no files matched!"
    else
        rm -f $def_out
        for file in $files_found
        do
            echo $file
            echo $file >> $def_out
        done
        echo "$def_out has create!"
    fi
}

function rm_files() {
    catlog=$1

    if [ -z $catlog ];then
        catlog=$def_out
    fi

    if ! [ -e $catlog ];then
        echo "$catlog not found"
        exit 0
    fi

    files=$(cat $catlog)

    for file in $files
    do
        if [ -e $file ]; then
          echo "rm $file"
          rm -f $file
        else
            echo "not exist: $file"
        fi
    done
    mv -f $catlog ${catlog}_done
}

if [ $# -eq 0 ]; then
    usage
elif [ $1 == "-d" ]; then
  rm_files $2
elif [ $# -eq 1 ]; then
  find_files ./ $1
elif [ $# -eq 2 ]; then
  find_files $1 $2
else
    usage
fi

2013/06/08 补充：
上面的代码在 Redhat 5.8 运行没问题，今天在 Ubuntu 12.04 上运行时，遇到一些麻烦，两者语法略有差别，要做以下修改：

定义函数不再需要 function 关键字，去掉。
比较字符串相等不使用「==」，而是「=」，所以 elif [ $1 == "-d" ]; 要改成 elif [ $1 = "-d" ];
if [ -z $files_found ]; 这一句原本写得也不是很严谨，在 Redhat 下不会报错，在 Ubuntu 下会报错，要改成 if [ -z "$files_found" ];

Baurine

scribble

25 May 2013 改进的 rm

25 May 2013
改进的 rm