Programmer Think

Catalog   1. SED of Three Swordsmen 1.1. Fundamentals 1.1.1. Summary 1.1.2. grammar 1.2. List display 1.2.1. Add in/etc/passwd line 4 1.2.2. Append insert 1.2.3. delete 1.2.4. replace 1.2.5. Print Display 1.2.6. Multipoint Editing 1.2.7 Modify text content 2. AWK of Three Swordsmen 2.1. Summary 2.2. grammar 2.3. List 2.3.1. Se ...

1, Overview 1.1 cluster Cluster, also known as cluster It is composed of multiple hosts, which is external as a whole. It only provides one access entry (domain name or IP address), which is equivalent to a mainframe computer 2, Classification There are three types of target differences Load balancing clusterHigh availability clusterHi ...

shell_01 File expression if [ -f file ] If the file exists if [ -d ... ] If directory exists if [ -s file ] If the file exists and is not empty if [ -r file ] If the file exists and is readable if [ -w file ] If the file exists and is writable if [ -x file ] If the file exists and is executable Integer variable expression if [ int1 -eq int ...

etc is tampered with, resulting in viruses in the system Cause: The Alibaba cloud server I bought a year ago was not long after I bought it. Because I didn't take any security measures, I somehow hijacked the server and downloaded some mining scripts on it. The processing method at that time was simple and rough. I directly reset my Alibaba c ...

7. Conditional judgment Conditional judgment syntax format Format 1: test Conditional expression Format 2:[ Conditional expression ] #Pay attention to the spaces Format 3:[[Conditional expression]] #regular expression Relevant parameters of condition judgment Q: what do you want to judge? A: I want to judge the file type, wheth ...

gprof is used to analyze the time-consuming of function calls. It can be used to catch the most time-consuming functions in order to optimize the program.The - pg parameter must also be added when linking gcc, so that gmon.com can be generated after the program runs Out file for gprof analysis.gprof does not support multi-threaded programs by d ...

Virtual File System VFS (Part 2) 9 catalog item object VFS treats directories as files, so in the path / bin/vi, bin and vi belong to files - bin is a special directory file, vi is an ordinary file, and each component in the path is represented by an index node object. Although it can be uniformly represented by index nodes, VFS needs to ofte ...

SSH port forwarding - case, command and server configuration Three forwarding types Local forwarding - LRemote forwarding - RDynamic forwarding-D Simple understanding: the three machines of ABC and AC cannot communicate directly, but B can communicate with AC respectively, so AC forwards and communicates through B Local SSH port forwarding ...

Linux mysql5.7 installation - super detailed Step: the installation of this article is version 5.7 Step reference video - ruoze explanation The installation steps should be roughly described below during the interview check whether Mysql is installed or running in the systemdownload mysql source package and decompressionCreate administrativ ...

Case overview Recently, I just finished an IDC project. There are just two h3cs as storage switches to provide 10Gb iSCSI mounting. There was little contact before H3C stacking. This time, it is just used as a record, including the pit that is easy to hit in the middle of the configuration Introduction to IRF Different from the traditional p ...