Linux

1. Embedded Linux logo Display principle Embedded Linux is directly based on the framebuffer. Direct display of an image in PPM format. It is completed in the Kernel/drivers/video/fbcon.c Fbcon_show_logo (), with a maximum color of 224 colors and

Kernel version: 2.6.34 UDP packet Reception The reception of UDP message can be divided into two parts: the protocol stack receives the UDP message, inserts the corresponding queue; the user calls Recvfrom () or recv () system call to take out the

Kernel version: 2.6.34 The previous routing table http://blog.csdn.net/qy532846454/article/details/6423496 describes the structure of the routing table and the creation of the routing table. The following are the details of the use of some routing

The function of the DF command in Linux is to check the disk space footprint of the filesystem on the Linux server. You can use this command to get how much space the hard disk is occupied and how much space is left. 1. Command format: DF [Options]

The tail command writes the file to the standard output from the specified point. Using the-f option of the tail command makes it easy to refer to the changing log file, Tail-f filename will display the tail contents of the filename on the screen,

I. Description Similar to the dynamic link library in Windows, Linux also has a corresponding shared library to support the reuse of code. *.dll is in Windows and *.so is in Linux. Here's a detailed description of how to create and use a shared

As a desktop system such as Ubuntu, the default login account does not have root permissions, in order to enhance the permissions to perform tasks, we generally use the sudo+ command to execute, but it is not difficult to find that we generally have

The steps are as follows: 1, create a file to store commonly used commands, such as/root/history.txt, write the common commands as text, each command occupies one line 2, run history-c in the terminal, clean up the messy history record 3, run

A process is an instance of the execution of a program, that is, the collection of data structures to which the program has been executed. From the kernel point of view, the purpose of the process is to serve as the basic unit of allocating system

Zombie does not take up memory and does not occupy the CPU, on the surface we can not care about their existence, however, in fact, the UNIX system limits the maximum number of processes that can exist at one time at a time. If the program does not

1. Introduction In Linux, there is no exec () function, exec refers to a set of functions, a total of 6, respectively: #include extern char **environ; int execl (const char *path, const char *arg, ...); int EXECLP (const char *file, const char

One: Linux kernel: The operating system is a low-level support software used to deal with hardware and provide a limited set of services for user programs. A computer system is a symbiotic body of hardware and software that is interdependent and

First, Fcntl function Function: Manipulate file descriptors to change the properties of an open file int fcntl (int fd, int cmd, .../* arg */); The value of CMD can be as follows: Copy file descriptor F_DUPFD (Long) Set/Get File descriptor

Whether the device that is connected to the bus on the CPU or inside the CPU has its own address range, can access the same as access to memory, many architectures (such as ARM) operate the device in this way, called memory mapped I/O

Find a directory with name Conf #find/directory-type d-name conf Note that the type may be b,c,d,l ... Find files with permissions of 755 #find/directory-perm 755-print If you use octal, you can use the #find/directory-perm-007-print (same as

Problem: Our company has two Linux servers, one hard drive per server. So the question of backup is particularly important. We have a MySQL database installed. Of course, but also to solve the problem of MySQL backup. Purpose: Host machine

Linux is a superior open source operating system, with its performance and visibility increasingly high, the most important is the price unmatched advantage, many manufacturers began to launch Linux laptops, and this trend has become increasingly

A Overview This article describes a way to transfer files between a Linux host and a Windows host. Because sometimes, some files in a Linux host may be used in a Windows environment. For example, in the Linux host grabbed some pictures, want to

I. Common ACL list types ACL definition Instance ACL LAN1 src 192.168.1.0/24 ACL PC1 src 192.168.1.66/32 ACL Blk_domain dstdomain. qq.com. kaixin001.com ACL work_hours time MTWHF 08:30-17:30 ACL Max20_conn maxconn 20 ACL Blk_url url_regex-i

Sometimes, the cloning function of the kvm/vmware virtual machine is used to quickly replicate the installed system. But after cloning, will find no eth0 network card. Workaround: 1. Edit/etc/udev/rules.d/70-persistent-net.rules File The