Linux

I. features: L self-compiled kernels run faster (with fewerCode) L The system will have more memory (the kernel part will not be exchanged to the virtual memory) L compilation of unnecessary functions into the kernel may increase the

About vi VI editor Learning The VI editor has three modes: Command mode, input mode, and last line mode. In any mode, you can press [ESC] to return to the command mode. 1. vi Enter VI directly to view the VI version information. 2. VI

Default firewall rules Deny and deny a packet IPFirewall data packet transmission In the IP firewall, three built-in filter rule chains are used. All data packets arriving at the interface are filtered according to the input rule chain.

ArticleDirectory Option Example TIPS: Display or set the CMOS time Hwclock [Options]   Option -R: the default option. Read and print the CMOS time. -S: Set the CMOS time to the system time. -W: set the system time to

Sometimes we need the Linux system to automatically load some scripts or system services when it is started. You can perform this operation in three ways: Ln-s creates a soft link for/etc/init. d/rc *. d In the/etc/rc. d/rc *. d directory (*

PATH is an environment variable. To check the current environment variable in uppercase, set echo $ path: Export Path =/usr/local/sbin:/usr/local/bin:/sbin:/bin: /usr/sbin:/usr/bin or export Path = path:/XXX is invalid after it is logged out. Keep

In Linux, the file attribute is not hidden. file or directory, such. bashrc is hidden and cannot be seen with LS. You must use LS-a l or ll to see it. Rename the file to change the status ...... For example, if there is a. a file, use LS-A or ll

Translating boot sequence into Chinese is the guiding sequence and Starting sequence. It is an important knowledge point for learning Linux and a basic knowledge point. Take notes. Linux boot sequence: 1. Load BIOS (hardware information) Load

Interesting Linux Command Line Functions 1. Linux "SL" command line Although "SL" represents "Steam Engine Head", it is used to remind command line controllers not to turn "ls" into "SL ". Let's see what happens when we run this command in the

Use the Linux built-in firewall to implement the following eight requirements: 1. reject all FTP packets from external networks, but still allow internal ftp.2. allow SSH remote connections but deny telnet.3. deny ping.4. reject all traffic coming

1. Install JDK Download JDK directly from Sun: The http://java.sun.com/j2se/1.4.2/download.html provides two downloads: 1. rpm in self-extracting file (j2sdk-1_4_2_04-linux-i586.bin, 32.77 MB) This is a self-extracting file, installed on Linux

(1) Write a dynamic link library in Linux. Generally, the static Link Library is compiled with the source file to generate executable files. Dynamic Link Library is not, it is a compiled file (static is not), only whenProgramWhen running (but the

ArticleDirectory Modify permissions in digital notation Modify permissions in text notation I. Linux File Permissions Each Linux file has four types of access permissions: readable (R), writable (W), executable (x), and

Interrupt and interrupt handlingProgram 1. interrupted An interrupt is essentially a special electrical signal sent to a processor by a hardware device. After the processor receives the interruption, it immediately reflects the arrival of the

Process Scheduling 1. Policy Processes can be divided into I/O and processor consumption types. The former refers to the process that is usually running when it is used to submit I/O requests or wait for I/O requests. The latter mostly uses the

Process Management 1. Process Descriptor and Task Structure Processes are stored in a two-way cyclic linked list called a task list. Each item in the linked list contains all the information of a specific process. Its type is task_struct, known

In shell, you can directly use 'env' or 'echo $ Home' to obtain or set environment variables.C LanguageHow is it implemented? There are two main functions and an environ variable (String Array ): Char* Getenv (Const Char* Name)IntPutenv

Do not use JavaScript for any form of commercial purposes. PS: Sold on the Pat listThis book describes how to build a firewall in a Linux operating system, as well as intrusion detection and system security technologies. The main content includes:

Description of matching parameters: -- Source (-s) ----------- match the source IP address -- Destination (-d) --------- match the destination IP address -- Protocol (-p) ----------- matching protocol -- In-interface (-I) ---------- entry --

When we use the "who" or "w" command on a Linux terminal, we will always see a long list of users. At this time, do you really want to send a message to him/her. If she is a long-time-honored MM, and you see her, she is also shy. Do you want to send