Linux

The Linux kernel driver has been debugged for countless times. There are also some experiences about Linux's dead-end methods.   1. the type is brittle. Features: No prompts, No prompts in/var/log/messagesxxx. Cause: you are not playing well on

Embedded Linux kernel optimization and cropping Optimization 1. Remove support for Virtual MemoryGeneral setup --->[] Support for paging of anonymous memory (SWAP) Optimization 2. Use the default I/O scheduler to cancel other schedulers.-*-Enable

  1. Modify the Linux Startup Mode (text or XWindow) VI/etc/inittab, find ID: X: initdefault: one line, x = 3 is text mode x = 5 is XWindow mode, restart the machine to take effect 2. How to exit man? Q 3. How to check the kernel version

Source: http://www.top-e.org/jiaoshi/class/ The functions defined in the export_symbol label are public to all kernel code. You can directly call the functions in the kernel module without modifying the kernel code. You can also manually modify the

Function Description:   Kthread_create: Create a thread. Struct task_struct * kthread_create (INT (* threadfn) (void * data), void * data, const char * namefmt ,...); After a thread is created, it does not run immediately. Instead, it needs to pass

Summary of file-related structs in linux2.6x kernel I. Common file-related structs Taking 2.6.22 as an example, other 2.6.x versions may be adjusted, but the changes are not significant.1.1 struct File Struct file struct is defined in

Segmentation and paging are two ways to divide or map addresses. The differences between the two are as follows: A) The page is the physical unit of information, and the page is the discrete distribution method,To reduce the external zero header

Thank you for choosing http://kb.cnblogs.com/page/76622 !!! Today, a friend went to a good foreign company to interview for a Linux development position. The interviewer gave the following question: The following C program is provided and compiled

TUN/TAP is a set of virtual network devices implemented by pure software. Tap indicates a virtual ethernet device that works on a L2 network and can directly process Ethernet frames. Tun indicates a virtual point-to-point device that works on a l3

Created Thursday 17-November 20Introduction: Dnw is a tool for writing software to the arm board through USB. It was developed by Samsung, but this software is only available in windows. on the arm9house Forum found that someone has rewritten a

Previously, we talked about libpcap packet capture, especially in the case of a gigabit network, which results in a large number of packet loss and a long time of searching on the Internet. This is probably a method like pf_packet + MMAP, napi, and

[Notes: kernel version Linux-2.6.30] Setup_arch execution is called by start_kernel: Start_kernel [init/Main. C] --> setup_arch (& command_line) [ARCH/ARM/kernel/setup. C] void __init setup_arch(char **cmdline_p){struct tag *tags = (struct tag

Objective: To study USB in depth and take notes here. Welcome to the discussion. [Linux 3.2] [Driver/USB/CORE/USB. C] USB is a sub-system of Linux, and its initialization function is modified by subsys_initcall. The initialization code is as

[Notes: kernel version Linux-2.6.30] Parse_cmdline is mainly used to parse command line parameters. Implementation principle: an infinite loop first searches for the first space. If yes, check whether the string before the space matches early_param.

Use delayed_workqueue in the Linux DRIVER: In the driver, sometimes the interrupt cannot be used (this is rare). In this case, delayed_workqueue can play a huge role. You can also use other similar kernel APIs, such as timer. The use process of

In Linux, sqlplus cannot use the up/down key to call previously entered commands. To use this function, you need to install rlwrap. The settings are as follows: Install rlwrap: # Tar-zxvf rlwrap-0.37.tar.gz # Cd rlwrap-0.37 #./Configure # Make

Botnets in the system must be recycled by the wait system. The following describes how to use wait in practice: The wait function is prototype: # Include /* define the pid_t type */ # Include Pid_t wait (int * status ); Returned value: if the

Fork creates a new process. The newly created process is a sub-process. It is a copy of the code of the parent process and is usually used on the server where multiple processes are processed, you can also run independent code in a sub-process.You

Pthread_join causes one thread to wait for the end of another thread. Without pthread_join in the Code, the main thread will soon end and the entire process will end, so that the created thread will end without a chance to start execution. After

Abstract: little story about novel form maintenance. Management inspiration: leaders like employees who seem very busy. Management: self-respect. When I went to work on Monday, the O team lead asked the C team lead to use the Linux boot CD and