在linux中为某些用户检索infor

Question

我有这个代码来生成用户帐户信息。问题是，我有一个用户名行，您将在其中键入用户名，并仅检索该指定用户名的信息。但是，代码检索系统上所有用户的信息。

#! /bin/bash
#This script returns import information about the  user name on the system

echo "PLease enter  name to continue:"

read SuppliedName
for user in $(cut -d: -f1 /etc/passwd)
#while [ "$SuppliedName" == "$USER" ]
do
IFS=$'\n'

userinfo=$(grep $user: /etc/passwd)

comment=$(echo $userinfo | cut -d: -f5)
home=$(echo $userinfo | cut -d: -f6)
groups=$(groups $user | cut -d: -f2)

#Skip users that do not have '/home' in the path to their home directory
if [ $(echo "$home" | grep -v '/home/') ]
then
    continue
fi

echo "Username: $user"
echo "User Info: $comment"
echo "Home Directory: $home"
echo "Groups: $groups"

echo "Disk usage: $(du -sh $home)"

last=$(last $user | head -1)
if [ $( echo $last | wc -c ) -gt 1 ]
then
    echo "Last login: "
    echo "$last"
else
    echo "User has never logged in!"
fi
echo ""
echo "--"
echo ""
done

Answer 1

1. 您缺少了$user和$suppliedName之间的比较，因为您在/etc/passwd上迭代以获取所有用户数据，所以可以打印出来。
2. grep $user: /etc/passwd将对包含“$user：”的所有行进行grep，包括以该名称开头具有GECOS的用户(正确的正则表达式是^$user:)。
3. 此代码只检查本地用户，因此不检查LDAP。更干净的方法是使用getent。

总之，我会在这方面使用finger。或将主循环重写为：

getent passwd $suppliedName | ( 
    IFS=: 
    while read UNAME SHADOW UID_ GID GECOS HOME SHELL ; do 
        # Your code goes here
    done )

Answer 2

你可以用另一种方式做到这一点，用更少的努力，更优雅地处理不匹配的问题。

#!/bin/bash

printf "PLease enter name to continue: "    ## use printf

read -r name

info="$(grep "^$name" /etc/passwd)"         ## read line into info

if [ -n "$info" ]; then     ## test that info is not empty, then call awk
    awk -F : '{printf "Username: %s\nUser Info: %s\nHome Directory: %s\n", $1, $5, $6 }' \
    <<< "$info"             ## use herestring to feed data to awk
    printf "Groups: %s\n" "$(groups "$name")"       ## use groups
else
    printf "error: name not found '%s'\n" "$name"   ## handle error/no match
fi

示例使用/输出

$ bash getuser.sh
PLease enter name to continue: david
Username: david
User Info: David C. Rankin
Home Directory: /home/david
Groups: david : david adm lp sys uucp wheel vboxusers