unix commands

1.wget---Download files, through HTTP or FTP protocol, support the continuation of the breakpoint usage:wget [opition] url Sample:wget http://down.cnblogs.com 2.SCP---Sync file, go to SSH protocol tunnel USAGE:SCP target host:/target file or

Http://tool.chinaz.com/Tools/unixtime.aspx now the Unix timestamp (Unix timestamp) is1440732364Unix Timestamp (Unix timestamp) → Beijing Time →unix timestamp (Unix timestamp) How do I get the current UNIX timestamp (

JS gets the Unix time stamp The Unix timestamp (Unix timestamp), or Unix time (Unix times), POSIX time (POSIX times), is a time representation, defined as the total number of seconds from GMT January 01, 1970 00:00 00 seconds to the present.

); fcntl (fd, F_DUPFD, fd2); because of its non-atomic operation, dup2 and fcntl have some different errno 13. sync, fsync, and fdatasync The traditional Unix system has a buffer or a page cache in the kernel. Most disk I/O operations are performed through the buffer zone. When we write data to a file, the kernel usually copies the data to the buffer first, then enters the queue, and then writes the data to the disk later. This method is calledDelay

UNIX, Linux, BSD-Unix, and MACOs are all computer operating systems. The earliest Unix was developed in 1973 by Dennis Ritchie at the Bell Laboratory of att, which was all written in C language.After the successful development of the original UNIX, people thought it was very useful. As a result, two major branches e

Often people ask what is the difference between "linux and UNIX? ","linux is UNIX? 」。The answer is generally "linux is a Unix-like development of Os","linux and Unix similar but not a os".There are some stories about "linux and unix".First, "

Advanced Programming in the UNIX Environment (third edition) is a well-known programming book for Unix systems.However, the code example in the book, in order to correctly compile the run, you need to prepare the work:1. Download the source codePortal: http://apuebook.com/code3e.html2. Extracting source codeTar XF src.3e.tar.gz3. Install Libbsd-devel, otherwise compile the wrong returnYum Install Libbsd-de

Chapter 23rd UNIX File SystemNamed pipe Mkfifo:mkfifo [-M mode] pipe. Named pipes must be created explicitly and will not disappear (the RM command can be removed).The proc file is a pseudo-file used to access kernel information. For example, if a process ID is 1952, the process-related information can be found in a file in the/proc/1952 directory.The VFS (virtual file system) implements the details of file processing.24th Directory Operations~ Repres

1:unix file Type-3 typesNormal files (regular files): Text files (plain text, scripts, source programs, configuration files, HTML, etc.), binary files (multimedia files, databases, etc.)Directories: for organizing filesPseudo-file: does not store data for the purpose of providing a service. Divided into three kinds:Special files: Device drivers, file representations of physical devices (keyboards, monitors, etc.)Named pipes: Directing the output of on

Simple UNIX-prepaster and unix-based prepasterIn Linux, the current process scheduling algorithm is the CFS algorithm, which replaces the previous time slice rotation scheduling algorithm. The CFS algorithm smooths the dynamic priority calculation process, this allows the entire system to be preemptible by any execution entity at any time. In fact, this is the basic principle of the time-sharing system. Ima

I have been engaged in pythonWeb development for a year. Now I am confused. I mainly work on curd, that is, how to obtain data, and then present it to the front-end page. The framework uses django, optimization means adding memecache. Pay attention to this when querying the database. Currently, there are a lot of tangled issues: 1: the programming of process threads, how to use it in practice 2: network programming problems, the design and implementation of high-performance servers, I can't unde

Introduction: Do you know that blogging works in conjunction with UNIX (R)? UNIX's built-in Web and text processing tools enable you to create blogs quickly and easily. Explore some handy tips for improving the creative skills of UNIX blogs. UNIX® has a lot in common with web blogs or blogs. In addition to being the native environment for most Web servers and th

A simple UNIX-Linux CFS annotation, unix-linuxcfsThis series is named simple UNIX, but it also includes the details of various UNIX-like systems. This series of articles are based on my study notes over the past few years, focusing on the analysis of various UNIX,

Build an advanced programming and learning environment in UNIX --- apue. h, unix --- apue. h This course has just learned advanced programming in UNIX, but has encountered many problems when setting up the programming environment of this book. Fortunately, there are various solutions on the Internet that allow me to finally solve the problem. I would like to than

PROFTPD is a UNIX platform or Unix-like platform (such as Linux, FreeBSD, etc.) FTP server program, it is under the Free Software Foundation's copyright notice (GPL) under the development, release of free software, that is, anyone to comply with the GPL copyright notice, Can modify the source start code at will. The PROFTPD design goal is to implement a secure and easily configured FTP Server. At present

UNIX advanced environment programming (14) file IO, unix programming 14io Spring is coming. In addition to work and study, everyone must exercise and exercise more. Haidao, which was shot in haidao Huaxi, yuandu ruins park last weekend. Go to the topic. O_DIRECT and O_SYNC are flags that the system calls open. Open a file with a specific file descriptor by specifying the flag parameter.These two flags hav

I recently studied Unix programming art. The first chapter is very good. It tells us a lot about the history and philosophical basis of Unix. The most important part is the 17 design principles mentioned. I know many principles, but I have never summarized them in such detail. Most of the content below comes from the book "Unix programming art", which is a small

Java Time Javascript Math. Round (new date (). gettime ()/1000)The unit of the value returned by gettime () is millisecond. Microsoft. NET/C # Epoch = (datetime. Now. touniversaltime (). ticks-621355968000000000)/10000000 MySQL Select unix_timestamp (now ()) Perl Time PHP Time () PostgreSQL Select extract (epoch from now ()) Python Import time first and then time. Time () Ruby Obtain

[Test Tool] a tool that converts Unix time to general time. The test tool is unix. A tool for converting Unix time to general timeDemo effect: Click convert: Source code: Function calctime2 () {var time = invalid argument Doc ument. getElementById ("inpTime "). value; if (time = "") {alert ("time is blank, enter"); return;} if (isDigit (time) = false) {alert ("t

UNIX domain sockets are used to communicate between processes running on the same machine.UNIX domain sockets provide both stream and datagram interfaces. Create a pair of non-named, interconnected UNIX domain sockets. Socketpair1. Naming unix domain sockets1) Socket address format, under Linux as shown in struct Sockaddr_un {sa_family_t sun_family; char sun_path