linux - 语句的含义 -du -sk * |sort -rn|head

Question

我在理解 Linux 命令的含义时遇到了麻烦du -sk * |sort -rn|head。我知道 du 用于显示磁盘使用情况，但我在理解命令的其余部分时遇到了麻烦。有人可以分解这里到底发生了什么吗？还可以建议一些好的资源来详细研究复杂的linux命令吗？

Answer 1

学习 Unix 命令的好资源是手册页。

man du：

Summarize disk usage of the set of FILEs, recursively for directories.
-B, --block-size=SIZE
       scale  sizes  by  SIZE  before printing them; e.g., '-BM' prints
       sizes in units of 1,048,576 bytes; see SIZE format below
-k     like --block-size=1K
-s, --summarize
       display only a total for each argument

man sort：

Write sorted concatenation of all FILE(s) to standard output.
-r, --reverse
       reverse the result of comparisons
-n, --numeric-sort
       compare according to string numerical value

man head：

Print  the  first  10 lines of each FILE to standard output.  With more
than one FILE, precede each with a header giving the file name.

该命令显示 10 个最大的目录或文件。

一步步：

#! /bin/bash

echo 'Create 20 files with random size.'
for i in {1..20}; do
  dd if=/dev/zero of="$i".data bs=1k count="$RANDOM"
done

echo 'Show the size of all 20 files in default units.'
du -s *.data

echo 'Show the size of all 20 files in KB.'
du -sk *.data

echo 'Show the size of all 20 files in KB and sort it in numeric order.'
du -sk *.data | sort -n

echo 'Show the size of all 20 files in KB and sort it in reverse numeric order.'
du -sk *.data | sort -rn

echo 'Show just the first 10 files of the previous output.'
du -sk *.data | sort -rn | head