unix and linux commands

[Origin] Daemon in linuxUnix is known to all. for example, httpd and MySQLd are commonly used, which are programs running in the resident memory, similar to services in Windows. Generally, the daemon processes are written using CC ++, that is, the child process is generated through fork. the parent process under the current shell is killed, and the child process is transferred to the background for running, in order not to generate output information on the terminal, syslog and other functions a

System-level IO in Linux/Unix Linux/Unix I/O: You can map a device to a file to allow the Unix kernel to provide a simple and low-level application interface. Linux/Unix IO systems call

Each device file supports system invoke IOCTL: Goal: Control a device Header files: #include Function prototype: int result = IOCTL (int fd, int operation [, Arg ...]); Parameters FD: File descriptor associated with file Operation: Type of operation ARG: Optional parameter Result:-1 is wrong; 0 is correct; In fact, the source or destination of any data is treated by UNIX as a file, and bas

' ibase=16;obase=1010; AC ' |BC (Linux)0172> Echo ' ibase=16;obase=1010; AC ' |BC (Unix)Output base is too large172Note here: This error will be reported when executing in Unix, but there will still be results.]$ Echo ' ibase=16; AC ' | Bc172Convert decimal to hexadecimal]$ echo ' ibase=10;obase=16;172 ' |BCAC]$ echo ' obase=16;172 ' |BCACconverting decimal to B

features of ANSI C (including the prohibition of some ASM inline typeof keywords to and Unix,vax and other preprocessing macros,-wallDisplay warning messages-fno-asmThis option implements part of the functionality of the ANSI option, which prohibits asm,inline and typeof as keywords.-o0-o1-o2-o34 levels of the compiler's tuning options,-o0 means no optimizations,-o1 defaults,-o3 highest level of optimization-GJust the compiler, when compiling, produc

This article describes how to apply a PHP script to correct the Linux or Unix system password. Required Tools and installation: you must install the following tools and software:-Shell script for password fixing;-Sudo access permission;-ApacheorLighttpdweb server;-PHP service This article describes how to apply a PHP script to correct the Linux or

On the linux/unix platform, it is not difficult to check which databases or instances exist on the OS. As some colleagues asked this question, I wrote down the method, someone may ask, but maybe another person may not. I hope it will help some friends who are not or just new. On the linux/unix platform, you can view th

Socket Chapter Reading notesHighly recommended Linux/unix system programming manual, known as the God book Beyond Apue.Backlog meaning#include int listen(intint backlog)The backlog parameter limits the number of pending connections (not accept), and within that number,connect will succeed immediately .The upper limit on Linux is 128, defined inUDP is connected to

Files written on Windows, opened under Linux or UNIX, each line will have more characters like ^m, because Windows is different from *nix's newline character, so let's see how the file format differs.To view file formats under Linux:# file filename# 20140304110001.csv:iso-8859 text//Not with ^m# 20140304110002.csv:iso-8859 text, with CRLF line terminators//with ^

experiment 3:unix/linux permissions and file management commands 1. Experimental purposes Unix/linux permissions and file management commands; The use of Unix/linux file system; Other commands related to file system administrati

The guy who is familiar with DOS is trying to make UNIX like DOS, One of them is to set the Unix prompt as $ p $ G. The following describes the method. The GNU bash (Bourne again shell) is more convenient for different shell settings)And KSh (Korn shell) and tcsh (enhanced version of CSH, CSH in Linux isSymbol connection ). The General Sh (Bourne shell) and CSH

The Linux/unix shell script, such as calling or executing Sql,rman, provides great convenience for automated jobs and multiple iterations, so Oracle is completed through the Linux/unix shellAnd is one of the essential skills of DBAs. This article calls SQL for the Linux/

A relatively safe Internet server, as an open-source operating system, once a security vulnerability is found in the Linux system, volunteers from around the world on the Internet will actively fix it. However, system administrators often cannot obtain and correct information in a timely manner, which gives hackers an opportunity. However, compared with the security vulnerabilities of these systems, more security problems are caused by improper config

"Unix/linux Network log analysis and Traffic monitoring" experimental environment download650) this.width=650; "src=" Http://s3.51cto.com/wyfs02/M02/53/C2/wKiom1Ru9IygmzgRAAQuIqyf7TA962.jpg "title=" Unix-linux123.jpg "alt=" Wkiom1ru9iygmzgraaquiqyf7ta962.jpg "/>1.Ossim 4.1 Virtual machine Download (for servers running on 2~4g memory)2.Ossim 3.1 Virtual machine do

Configure scp to transfer files between Linux and Unix without a password How to configure scp File Transfer To implement scp file transfer between Linux and Unix, you first need to configure scp. By default, scp requires a password. You can complete file transfer between Linux