sed & awk

看到过的最好的一个讲解sed & awk的PPT

http://www.cs.nyu.edu/~mohri/unix08/lect5.pdf

现在制作一个自己的版本的ls

sed_ls_fmt

s/^d/dir  /1
s/^-/file /1
s/([rwxs-]{3})([rwxs-]{3})([rwxs-]{3})/1 2 3/

awk_ls_fmt

NR != 1{
    size = 0
    unit = "B"

    if ($8 < 1024)
        size = $8
    else if($8 < 1024 * 1024)
    {
        size = $8/1024
        unit = "KB"
    }
    else if($8 < 1024 * 1024 * 1024)
    {
        size = $8/1024/1024
        unit = "MB"
    }
    else
    {
        size = $8/1024/1024/1024
        unit = "GB"
    }

    printf("%6s	link:%s	owner:%6s[%s]	group:%6s[%s]	others:[%s]	%6.2f %s	mtime:[%2s %2s %5s] %s
",
        $1,
        $5,
        $6,
        $2,
        $7,
        $3,
        $4,
        size,
        unit,
        $9,
        $10,
        $11,
        $12);
}

ls.sh

ls -l $1 | sed -f sed_ls_fmt | awk -f awk_ls_fmt

效果如下：

bash ls.sh ~

file    link:1    owner:daniel[rw-]    group:daniel[r--]    others:[r--]     32.62 MB    mtime:[3月 28 17:33] pin-2.13-62732-gcc.4.4.7-linux.tar.gz

dir    link:2    owner:daniel[rwx]    group:daniel[r-x]    others:[r-x]      4.00 KB    mtime:[2月 12 20:01] 公共的

dir    link:2    owner:daniel[rwx]    group:daniel[r-x]    others:[r-x]      4.00 KB    mtime:[2月 12 20:01] 模板

dir    link:2    owner:daniel[rwx]    group:daniel[r-x]    others:[r-x]      4.00 KB    mtime:[2月 12 20:01] 视频

dir    link:2    owner:daniel[rwx]    group:daniel[r-x]    others:[r-x]      4.00 KB    mtime:[3月  7 15:00] 图片

dir    link:2    owner:daniel[rwx]    group:daniel[r-x]    others:[r-x]      4.00 KB    mtime:[2月 12 20:01] 文档

dir    link:2    owner:daniel[rwx]    group:daniel[r-x]    others:[r-x]      4.00 KB    mtime:[5月 22 17:50] 下载

dir    link:2    owner:daniel[rwx]    group:daniel[r-x]    others:[r-x]      4.00 KB    mtime:[2月 12 20:01] 音乐

dir    link:2    owner:daniel[rwx]    group:daniel[r-x]    others:[r-x]      4.00 KB    mtime:[3月  8 16:26] 桌面

add color theme to output:

NR != 1{
    size = 0
    unit = "B"

    if ($8 < 1024)
        size = $8
    else if($8 < 1024 * 1024)
    {
        size = $8/1024 
        unit = "KB"
    }
    else if($8 < 1024 * 1024 * 1024)
    {
        size = $8/1024/1024 
        unit = "33[;31mMB33[0m"
    }
    else
    {
        size = $8/1024/1024/1024 
        unit = "33[;34mGB33[0m"
    }

    if ($1 == "file")
    {
        $1 = "33[;34mfile33[0m"
    }
    else
    {
        $1 = "folder"
    }

    printf("%6s	link:%s	owner:%6s[%s]	group:%6s[%s]	others:[%s]	%6.2f %s	mtime:[%2s %2s %5s] %s
", 
        $1, 
        $5, 
        $6, 
        $2, 
        $7, 
        $3, 
        $4, 
        size, 
        unit,
        $9,
        $10,
        $11,
        $12);
}