Linux

Waiting queues are used in the Linux kernel to block or wake up a process, to synchronize access to system resources, and to implement latency functions Wait Queue interface function Introduction: #include //header file contains 1. Define,

1. Print Log function #include #define SPIDER_LOG (level, format, ...) do{\ if (level >= g_conf->log_level) {\time_t now = time (NULL); \ char Msg[max_mesg_len]; \ char buf[32]; \ sprintf (msg, format, # #__VA_ARGS__);

Divide CPU-process management Mpstat based on server's hardware processing resources-View CPU Usage Statistics PS-view process kill-send a signal to a process pmap-view the memory distribution of the process MEMORY-memory Vmsta T-view memory, swap

Sigprof.c /************************************************************* filename:sigprof.c filefunc:2 seconds to produce a single signal processing version:v0.1 author:sunrier date:2012-05-25 descp:linux under signal processing * * /#include

1 Find CommandThe Find command is a ubiquitous command, one of the most useful commands in Linux. The Find command is used to search for files in a directory (and subdirectories), and you can specify matching criteria, such as locating files by file

I. The concept of a port In Network technology, ports (port) include both logical and physical ports. Physical ports are physical ports, such as ADSL modems, hubs, switches, and interfaces used to connect to other network devices on the router, such

Recently read a little about the kernel of books, some harvest, now take out to share with you, improper place please advise Schema conversion Linux runs in real-time mode in the first half of the boot process, and the program runs using physical

Only nor Flash is available on the Development Board, so in order to implement the hierarchical file system, it is necessary to add nor Flash MTD driver support for Linux2.6.20. In fact, the workload is not very large because there are already

Today came into contact with an artifact Xshell, which is also used to remotely deploy Linux under Windows, which is convenient, but how to upload files as easily as using Securect. Through the query data Xshell not only can easily upload files, but

1, atexit () function registration function code, run the result: Process Analysis: The Atexit function registers three fun functions, waits 3 seconds, and then prints "Hello bit" (if the output part of the main function does not add \ n, the

1.man 2. If you want to see who is currently online, you can release who this directive3. If you want to see the online status of the network, you can release netstat-a4. The procedure for viewing background execution can be performed ps-aux5. The

Recently using Redhat Linux development, occasionally found an interesting phenomenon. When you log on to the system at the command line, the X-Letters in Linux will change slightly before and after the login. It will be a bit wider when you log in.

Supervisord's introduction: http://supervisord.org/introduction.html In simple terms: daemon, if your process has been running, suddenly hung up.So Supervisord can help you speed up the process and make it work. 1: Install Supervisord Easy_install

I.mx6ul--A detailed explanation of Linux system porting process Development platform: Zhuhai Ding-core D518--based on I. MX 6UL Latest System: u-boot2015.04 + linux4.1.15_1.2.0 cross-compilation tool: DCHIP-LINARO-TOOLCHAIN.TAR.BZ2 Source

Under Windows We can view the system information directly by right-clicking the computer's properties. So how do you view it in a Linux system? Here are some ways to view Enter "Uname-a" to display information about your computer and your operating

* * * * * system call: Open a file * * function prototype: int open (const char *filename,int flags,mode_t mode); * * Parameter:filename-> the file name (including path) to be opened flags-> how to open the Mode-> Create mode return value: ... * *

One, increase user useradd Useradd MyUser Execution will create a user named MyUser.The user created does not have home dir, and users who created it with the Ubuntu system cannot log in using the interface because there is no home dir. Use the

Reference file: \kernel\documentation\devicetree\booting-without-of.txt 1. File organization structure of the device tree DT's file organization structure as shown *.dts is the device organization that is summarized as a target device, and it

Kernel debugging 1. Print debugging, Release Dpdebug switch 2. Debugger 3. Query Concurrency and Race State if (copy_from 1. Signal Volume Cannot be used outside the kernel, the process cannot be obtained on the sleep queue, then wake

The high 20 bits of the page table entry point to the memory page base, and the page status and permissions are set to a low of 12 bits. If the page table entry has a present bit of 1, the corresponding page or page table has been loaded into the