Linux脚本不起作用

Question

I have the following code:

#!/bin/bash
# script.sh

awk -F: '{if ($3 > 500) {print $3}}' /etc/passwd
awk -F: '{if ($3 > 500) {
if (size = "$(du -s /home/$1)" > 10000) {
mkdir /home/copy/R$1
cp /home/$1 /home/copy/R$1
}
}}' /etc/passwd

The first awk prints all the users with the UID above 500. The second awk should create the directory /home/copy/Ruser, and copy all the files of the user directory in it, when the size of the user directory is above 10000, but it doesn't do anything, and there's no error when I run the script.

Answer 1

$( du -s ) is a shell syntax, not awk syntax. The following assigns the size of the home directory to size in gawk:

"du -s "$6" | cut -f1"  | getline size
if (size > 10000) {
    ...

Answer 2

Using awk for this is probably more trouble than it's worth:

#!/bin/bash

while IFS=: read user passwd uid gid info dir shell; do
  test $uid -gt 500 2> /dev/null || continue  # Skip if uid too low
  size="$(du -s $dir)"
  if test "$size" -gt 10000; then
    mkdir /home/copy/R$user
    cp /home/$1 /home/copy/R$user  # This probably won't work!
  fi
done < /etc/passwd