Linux

Test of the Linux self-brought mail commandStep 1:Send mail through the Mail command, found unable to send to the external mailbox, find the relevant instructions on the Internet, check the mail and MAILX version[Email protected] ~]# Rpm-qa|grep

1, 2015/07/30 When installing the JDK view version, found that the system installed other versions of the JDK, in order to avoid conflicts with my upcoming installation of the JDK, all want to put the system to all existing JDK removed before

1.2015/07/30 environment variables used to configure the JDK---------------------------------------------------------------------------------------------------------------

1. Users and Groups: User|group|othersUser Information file:/etc/passwd/User Management files:/etc/shadow/Group information file:/etc/group/2. File permissions1.linux file Properties Example: Drwxr-xr-x. 2 WXC wxc 6 March 29 20:00 Public1. The first

Device files:B: Block files, Unit-by-block, randomly accessed devices, such as disksC: Character file, in alphabetical order, to access linear devices, such as keyboardsLs-l View the device files, the original display size of the column is changed

UNIX History Lessons:Don't compete with low-priced, flexible solutions;The more open source the more prosperousFundamentals of Unix Philosophy:Let each program only do one thing, if there is a new task, then a new program, and do not add

Read/write LockThe book has the reader's code, I really do not bother to realize it again. Similar to the previous code.Multi-threaded asynchronous signal processingint Pthread_kill (pthread_t __threadid, int __signo) : Sends a signal. A second

Xshell cannot enter Chinese characters and is displayed ??, You may find that you cannot enter Chinese characters when using xshell. The entered Chinese characters will become "?? "At first, I thought it was a encoding problem. After reading the

Ubuntu Server sets PPTP client connection and ubuntupptp Install the PPTP Client apt-get install pptp-linux Set connection account information sudo vim /etc/ppp/chap-secrets $ Login_name is the login name; $ password is the login password; $ if

[Java Development] ubuntu Common commands and environment setup, ubuntu Common commands On the first day of study, today's content is relatively simple. It mainly involves some common commands and common operations on ubuntu. Later, we will discuss

Linux NFS Server installation and configuration, linuxnfs I. Introduction to the NFS service NFS is short for Network File System, that is, Network File System. An agreement for the use of distributed file systems, developed by Sun, was published on

High-availability LVS and keepalived model lvs Based on the keepalived dual-Master Model Background: Keepalived: the purpose of Keepalived is to check the status of the web server. If a web server crashes or a job fails, Keepalived will detect it,

Disable the firewall for Centos7 and for centos7 1. Directly disable the Firewall Systemctl stop firewalld. service # stop firewall Systemctl disable firewalld. service # disable firewall startup 2. Set iptables service Yum-y install

Linux daemon note (start if the specified process does not exist) and linux note   Recently, I want to create a daemon In debian. The daemon program is always running. I checked it online and found the Crontab mode and script writing mode. 　　Crontab

Set up ftp service in linux1. Configuration/Etc/passwd/Etc/group/Etc/vsftpd. conf # configuration file/Usr/sbin/vsftpd # Main Program/Etc/vsftpd/ftpusers # blacklist. You cannot log on to the ftp server as long as it is in the

Linux disk management notesDisk Management1. df view disk partition usage-L only display local disks (default)-A: displays the disk usage of all file systems.-H: Calculate the disk capacity in December 1024.-H: Calculate the disk capacity in

Linux crontab usage notes1. InstallService crond statusYum install vixie-cronYum install crontabs2. InstancePrint the current time to the log file every minute# Crontab-e*/1 ***** date>/tmp/date.txt# Tail-f/tmp/date.txt (this file is dynamically

Common Linux/Unix development auxiliary commands Highlights of many fragmented commands: 1. How to download ftp files through commands Read-s-p "Your passwd:" Passwd; wget -- user = YourUserName -- password = $ Passwd ftp: // IP/dir/file Read-s-p

Linux text processing commandsRegular Expression POSIX standard classifies regular expressions into two types1. Basic Regular Expression2. Extended Regular ExpressionsMost Linux applications and tools only support basic regular expressions.Basic

Linuxshell reads the file line by lineRead File linesCommand to replace code block redirection whilePipeline Code block redirection IFS=$'\n'for line in `ls -l`do (( count++ ))doneecho $count Note:When reading for, the system automatically uses