pipe file

In the front we talked about one way of interprocess communication, anonymous pipelines.We know that anonymous pipes can only be used between processes for parent-child relationships. So how can data be passed between processes without such a

from:http://blog.csdn.net/jasonliuvip/article/details/22600569Linux Network Programming IX: Splice function, efficient 0 copiesRecently looking at "Linux High Performance Server Programming", here to do a diary to motivate themselves, while sharing

The signal binding mechanism simply means that the external signal is converted to an internal IO event for processing. Since the signal capture function is globally bound, there is no way to bind the IO event and file descriptor as an IO event, and

Basic commandsFirst, the basic principles of Linux:1, consisting of a small program with a single purpose; a combination of small procedures to complete complex tasks;2, all documents;3, try to avoid capturing the user interface; (try not to

Linux PipelinesA pipeline is a communication device that allows one-way communication. The data is written from one end of the pipe and read out from the other end of the pipe. Pipelines are serial devices, and data is always read in the order in

Guide In Unix and its derivative, such as Linux, everything can be considered a file. Although it is only a general concept, it is true. If there is not a file, then it must be a running process. To understand this, for example, the

Basic Operations Command: PS-AJX/-AUX/-EF view inter-process status/relationships Top dynamic display of processes in the system Nice run/renice by the specified priority change the priority of the running process Kill-9 Kill Process

_bmap () 1. The _bmap () function is used to map a block of file data to the processing operation of the disk block. Because an I node corresponds to a file, so the logical block number of the I node map above is the logical block number stored in

interprocess communication (IPC) refers to a mechanism for exchanging data between two processes. The modern OS has a protection mechanism for the process, so two processes cannot exchange data directly and must be done through a mechanism.The role

"Conditional judgment"1. Judging by file type-B file to determine if the file exists and is a block device file (is a block device file is true)-c file to determine if the file exists and is a character device file (the character device file is true)

Standard file library under Linux Query file property header file Function int stat (const char *filename, struct stat *buf)Get file properties int fstat (int fd, struct stat *buf)function with stat, but entry is file descriptor int

The OS module that is first considered when we need to invoke the command of the system. Use Os.system () and Os.popen () to operate. But these two commands are too simple. Unable to complete some complex operations, such as providing input to the

Geth is the most commonly used tool (prerequisite development tool) in the development of [Ethereum Smart Contract] (HTTP://XC.HUBWIZ.COM/COURSE/5ABBB7ACC02E6B6A59171DD6), a multi-purpose command-line tool. Familiarity with Geth can allow us to have

Subprocess is intended to replace several other older modules or functions, such as: Os.system os.spawn* os.popen* popen2.* commands.* The simplest use of subprocess is to invoke the shell command, and also to invoke the program, and to interact

Recently, our boss asked me to write a daemon program to protect the server process. If the server is unfortunately dead, the Guardian can restart the application immediately. Google on the internet a bit, found that Python has a few modules can be

Shell Features 1. explain the commands entered by the user and return the results to the user. 2. shell is the interface program Tip between the user and the system: similar to command.com for batch processing in windows. 1. view the types of shell

There are currently three ways to execute cmd in the python I use: 1. Using Os.system ("cmd") The feature is that when executed, the program will play CMD on Linux execution information. Import osos.system ("ls") 2. Using the Popen module to

There are currently three ways to execute cmd in the python I use: 1. Using Os.system ("cmd") The feature is that when executed, the program will play CMD on Linux execution information. Import OS Os.system ("LS") 2. Using the Popen module to

In python development , we often need to execute commands to modify the relevant information. So how do you execute commands in Python for beginners? Today, we share 3 ways to execute Python commands.1. Using Os.system ("cmd")In Python, the most

Through the shell example to learn the syntax of the loop structure: the so-called useful is to learn to use it all the time. it is useless if you forget it. On the other hand, it is very likely that the leaders have great expectations for you. So