日常作業2

1、顯示當前時間，格式為hh:mm:ss,並儲存到檔案time.txt檔案中；

[root@localhost

desktop]# date +%t | tee time.txt21:
37:23[root@localhost
desktop]# cat time.txt21:
37:23

[root@localhost

desktop]# head -n 18 /etc/passwd | tail -n 4 
nobody:
x:99:99
:nobody
:/:/sbin/nologin
dbus:
x:81:81
:system message bus:/:/sbin/nologin
usbmuxd:
x:113
:113
:usbmuxd
user:/:/sbin/nologin
vcsa:
x:69:69
:virtual console memory owner:/dev:/sbin/nologin

[root@localhost

desktop]# sed -n '15,18p' /etc/passwd
nobody:
x:99:99
:nobody
:/:/sbin/nologin
dbus:
x:81:81
:system message bus:/:/sbin/nologin
usbmuxd:
x:113
:113
:usbmuxd
user:/:/sbin/nologin
vcsa:
x:69:69
:virtual console memory owner:/dev:/sbin/nologin

4、在student使用者下查詢/etc下passwd檔案，遮蔽錯誤輸出；

[student@localhost ~]$ find /etc -name passwd 2>/dev/null

/etc/pam.d/passwd
/etc/passwd

[student@localhost ~]$ find /etc -name passwd >/tmp/westos.out 2>/tmp/westos.err

[student@localhost ~]$ cat /tmp/westos.err
find: `/etc/dhcp': permission denied
find: `/etc/sudoers.d': permission denied
find: `/etc/selinux/targeted/modules/active': permission denied
find: `/etc/audisp': permission denied
find: `/etc/pki/ca/private': permission denied
find: `/etc/pki/rsyslog': permission denied
find: `/etc/audit': permission denied
find: `/etc/ntp/crypto': permission denied
find: `/etc/polkit-1/localauthority': permission denied
find: `/etc/lvm/backup': permission denied
find: `/etc/lvm/archive': permission denied
find: `/etc/lvm/cache': permission denied
find: `/etc/cups/ssl': permission denied
[student@localhost ~]$ cat /tmp/westos.out
/etc/pam.d/passwd
/etc/passwd

[student@localhost ~]$ cat /tmp/westos.all

/etc/pam.d/passwd
/etc/passwd
[student@localhost ~]$ find /etc -name passwd 2>&1 | tee /tmp/westos.all
find: `/etc/dhcp': permission denied
/etc/pam.d/passwd
find: `/etc/sudoers.d': permission denied
find: `/etc/selinux/targeted/modules/active': permission denied
find: `/etc/audisp': permission denied
find: `/etc/pki/ca/private': permission denied
find: `/etc/pki/rsyslog': permission denied
/etc/passwd
find: `/etc/audit': permission denied
find: `/etc/ntp/crypto': permission denied
find: `/etc/polkit-1/localauthority': permission denied
find: `/etc/lvm/backup': permission denied
find: `/etc/lvm/archive': permission denied
find: `/etc/lvm/cache': permission denied
find: `/etc/cups/ssl': permission denied
[student@localhost ~]$ cat /tmp/westos.all
find: `/etc/dhcp': permission denied
/etc/pam.d/passwd
find: `/etc/sudoers.d': permission denied
find: `/etc/selinux/targeted/modules/active': permission denied
find: `/etc/audisp': permission denied
find: `/etc/pki/ca/private': permission denied
find: `/etc/pki/rsyslog': permission denied
/etc/passwd
find: `/etc/audit': permission denied
find: `/etc/ntp/crypto': permission denied
find: `/etc/polkit-1/localauthority': permission denied
find: `/etc/lvm/backup': permission denied
find: `/etc/lvm/archive': permission denied
find: `/etc/lvm/cache': permission denied
find: `/etc/cups/ssl': permission denied

日常作業2017 7 19

小白一枚。題目如下 有兩個執行緒，乙個是存錢的，乙個是取錢的，實現乙個無限的存錢和無限的取錢功能，每次存錢存100塊，每次取錢取100塊，如果取出錢的金額大於賬戶餘額 則列印賬戶餘額不足，每次存完錢要休息500毫秒，每次取完錢休息1秒，要求每次執行完乙個訪問錢的過程，需要列印如下資訊 年 月 日 存...

日常作業2019 1 15

作業 實現簡易計算機，分別實現兩個整數 三個浮點數的加法運算 package com.job1 15 計算器 author administrator 2019.1.15 public class calculator 三個浮點數相加 param num1 param num2 param num3...

日常作業2019 1 9

預習 一，什麼是物件 物件是用來描述客觀事物的乙個實體。用物件導向解決問題是，面對現實世界中的物件進行分析與歸納，找出哪些物件與要解決的問題是相關額。例如，奧迪跑車 寶馬跑車 賓士轎車 保時捷跑車，雖然這幾個跑車都是物件。但是他們之間具有不同的特徵。具體來講就是品牌不同 不同 效能不同等。二，什麼是...