pipe

Efficient data transfer from Java to C++ on windows

淺唱寂寞╮ 提交于 2020-01-11 08:36:09
问题 I'm looking to stream lots of data (up to ~1 Gbit) from Java to a C++ application (both on the same machine). I'm currently using a FIFO on Linux but need a Windows solution too. The most cross-platform method seems to be a local socket, but: a) won't I get huge overhead from TCP checksumming and copying to & from kernel space, and b) won't the average user's firewall try to inspect the and maybe block the connection? It seems like a safer solution may be to use JNI and the Named Pipe API (\.

Gulp: Getting Started

妖精的绣舞 提交于 2020-01-11 00:58:05
https://github.com/gulpjs/gulp/blob/master/docs/getting-started.md 1. Install gulp globally: $ npm install --global gulp 2. Install gulp in your project devDependencies: $ cd C:\Work\MyProject $ npm install --save-dev gulp 3. Install gulp-concat $ npm install --save-dev gulp-concat 4. Create a gulpfile.js at the root of your project: var gulp = require('gulp'), concat = require("gulp-concat"); gulp.task('packScripts', function() { gulp.src('Scripts/*.js') .pipe(concat('all.js')) .pipe(gulp.dest('Scripts')); }); gulp.task('packStyles', function() { gulp.src('Content/*.css') .pipe(concat('all

Image processing pipeline - Part

你说的曾经没有我的故事 提交于 2020-01-10 20:02:08
Image processing pipeline - Part C (10%) Complete your program by implementing pipefile parsing and command-line argument parsing. Pipefile parsing (5%) Your program should be able to parse an input text file, which we can call the pipefile. The pipefile describes a complete processing pipeline using nodes in a sequence. The following pipefile, pipe1.txt , is given as an example: Your program should be able to parse any pipefile that describes nodes that you have implemented in part A. In order to parse a pipefile, you will need to implement a method that reads in a pipefile, and then creates

进程间通信(一)

坚强是说给别人听的谎言 提交于 2020-01-10 03:40:06
进程间通信 一、进程间通信简介 1.进程间是相互独立的,每个进程都有自己的进程虚拟地址空间,二进程通讯需要介子,使得两个进程都能访问的公共资源; 2.进程间通讯的目的: 数据传输:一个进程需要将他的数据发送给另一个进程 资源共享:多个进程间共享同样的资源 通知事件:一个进程需要向另一个或一组进程发送消息,通知它们发生了某种事件(如子进程退出时要通知父进程回收其资源等) 进程控制:有些进程希望完全控制另一个进程的执行,此时控制进程希望能够拦截另一个进程所有陷入和异常,并能及时的知道他的改变状态 二、进程间通讯的发展及分类: 1.管道 匿名管道pipe 命名管道 2.System V进程间通讯 System V消息共享队列 System V共享内存 System V信号量 3.POSIX进程间通讯 消息队列 共享内存 信号量 互斥量 条件变量 读写锁 三、管道 1.什么是管道: 管道是内核中的一块内存 ,构成一个队列, 使用一对文件描述符来进行访问管理这个内存 ,读文件描述符相当于从这个内存中取数据,写文件描述符相当于往这块内存中写数据 2.匿名管道 匿名管道的创建 int pipe(int pipefd[2]); 功能:是创建一个无名管道; 参数:是两个输出型参数,fd表示文件描述符数组,其中fd[0]端表示读端,fd[1]端表示写端。 返回值:创建成功返回0;失败返回错误码。

进程通信之对象-无名管道

生来就可爱ヽ(ⅴ<●) 提交于 2020-01-10 00:06:34
无名管道(管道=队列):在系统中无不存在这样一个文件名 例子1:用pipe()函数创建一个无名管道,实现一个进程向管道中读写信息;建立no_name_pipe1.c内容如下 #include"unistd.h" #include"sdtio.h" #include"stdlib.h" #include"string.h" int main() { int fd[2]; int ret;//管道描述符 char write_buf[]="hellolinux!";//要向管道写入的信息 char read_buf[128]={0};//读缓存 ret=pipe(); if(ret<0) { printf("create a pipe failure\n"); return -1; } printf("create pipe succcess 写端fd[1]=%d ,读端fd[0]=%d\n",fd[1],fd[0]); //向管道写入信息 write(fd[1],write_buf,sizeof(write_buf)); //start read from pipe read(fd[0],read_buf,128); printf("read_buf=%s\n",read_buf); //关闭管道两端 close(fd[0]); close(fd[1]); return 0; }

Use pipe without feeding first argument

旧时模样 提交于 2020-01-09 10:18:07
问题 Is the %>% pipe operator always feeding the left-hand side (LHS) to the first argument of the right-hand side (RHS)? Even if the first argument is specified again in the RHS call? Say I want to specify which variable to use in cor() : library(magrittr) iris %>% cor(x=.$Sepal.Length, y=.$Sepal.Width) But this fails, it looks like it call something like cor(., x=.$Sepal.Length, y=.$Sepal.Width) ? I know I could use instead iris %$% cor(x=Sepal.Length, y=Sepal.Width) But wanted to find a

How to use pipe within -exec in find

独自空忆成欢 提交于 2020-01-09 10:14:53
问题 Is there any way to use pipe within an -exec in find? I don't want grep to go through whole file, but only through first line of each file. find /path/to/dir -type f -print -exec grep yourstring {} \; I tried to put the pipelines there with "cat" and "head -1", but it didn't work very well. I tried to use parenthesis somehow, but I didn't manage to work out how exactly to put them there. I would be very thankful for your help. I know how to work it out other way, without using the find, but

get command output in pipe, C for Linux

眉间皱痕 提交于 2020-01-09 05:33:25
问题 I need to run a Linux CLI command and get its stdout output from C. I can use pipe() to create a pipe, then fork/exec, redirecting child's stdout descriptor into the pipe before calling exec(), and reading from the pipe in parent. Plus I'll need to wait on the child. Is there a simple call to do fork + redirect + exec + wait, like system() does fork + exec + wait, only system() doesn't do the redirect. There's popen(), which does fork + redirect + exec, but doesn't do wait, so I can't get

Pipe character in Python

别说谁变了你拦得住时间么 提交于 2020-01-08 13:20:34
问题 I see a "pipe" character ( | ) used in a function call: res = c1.create(go, come, swim, "", startTime, endTime, "OK", ax|bx) What is the meaning of the pipe in ax|bx ? 回答1: It is a bitwise OR of integers. For example, if one or both of ax or bx are 1 , this evaluates to 1 , otherwise to 0 . It also works on other integers, for example 15 | 128 = 143 , i.e. 00001111 | 10000000 = 10001111 in binary. 回答2: This is also the union set operator set([1,2]) | set([2,3]) This will result in set([1, 2,

java.io.IOException 断开的管道 解决方法 ClientAbortException: java.io.IOException: Broken pipe

醉酒当歌 提交于 2020-01-07 19:06:12
java.io.IOException 断开的管道 解决方法 ClientAbortException: java.io.IOException: Broken pipe 今天公司技术支持的童鞋报告一个客户的服务不工作了,紧急求助,于是远程登陆上服务器排查问题。 查看采集数据的tomcat日志,习惯性的先翻到日志的最后去查看有没有异常的打印,果然发现了好几种异常信息,但是最多还是这个: 24-Nov-2016 09:54:21.116 SEVERE [http-nio-8081-Acceptor-0] org.apache.tomcat.util.net.NioEndpoint A c c e p t o r . r u n S o c k e t a c c e p t f a i l e d j a v a . i o . I O E x c e p t i o n : T o o m a n y o p e n f i l e s a t s u n . n i o . c h . S e r v e r S o c k e t C h a n n e l I m p l . a c c e p t 0 ( N a t i v e M e t h o d ) a t s u n . n i o . c h . S e r v e r S o c k e t C h a n n