pipe

Using subprocess to get output of grep piped through head -1 [duplicate]

由 让人想犯罪 __ 提交于 2020-01-04 06:24:04
问题 This question already has answers here : 'yes' reporting error with subprocess communicate() (3 answers) How to use `subprocess` command with pipes (7 answers) Closed 4 years ago . The gist of what I'm trying to do is this: grep -n "some phrase" {some file path} | head -1 I would like to pass the output of this into python. What I've tried so far is: p = subprocess.Popen('grep -n "some phrase" {some file path} | head -1',shell=True,stdout=subprocess.PIPE) I get back a lot of messages saying

Using subprocess to get output of grep piped through head -1 [duplicate]

由 本小妞迷上赌 提交于 2020-01-04 06:21:09
问题 This question already has answers here : 'yes' reporting error with subprocess communicate() (3 answers) How to use `subprocess` command with pipes (7 answers) Closed 4 years ago . The gist of what I'm trying to do is this: grep -n "some phrase" {some file path} | head -1 I would like to pass the output of this into python. What I've tried so far is: p = subprocess.Popen('grep -n "some phrase" {some file path} | head -1',shell=True,stdout=subprocess.PIPE) I get back a lot of messages saying

Redirecting STDOUT of a pipe in Perl

由 邮差的信 提交于 2020-01-04 06:14:31
问题 I feel as though there should be a simple way to do this, but searching around gives me no good leads. I just want to open() a pipe to an application, write some data to it, and have the output of the subprocess sent to the STDOUT of the calling script. open(my $foo, '|-', '/path/to/foo'); print $foo 'input'; # Should behave equivalently to "print 'output'" close($foo); Is there a simple way to do this, or have I hit upon one of the many "can't get there from here" moments in Perl? 回答1: The

how to import with roxygen packages the pipe operator %>% from dplyr

由 我怕爱的太早我们不能终老 提交于 2020-01-04 05:53:42
问题 I want to build a package with some functions i wrote. Now my problem is, that i cannot use the pipe-operator %>% with dplyr. I create the package with roxygen2. If i write the dplyr-commands without %>%, everything works fine. inside the code: #' #' @import dplyr readr mailR writexl #' @importFrom dplyr %>% #' @name %>% #' #' @export #' I wrote: DESCRIPTION LazyData: true RoxygenNote: 6.0.1 Imports: dplyr roxygen2 generates: NAMESPACE ... importFrom(dplyr,"%>%") ... 回答1: Usually you would

Redirect stdout of one process to two processes

由 ♀尐吖头ヾ 提交于 2020-01-04 04:55:58
问题 Im having big troubles in doing what i said in title. Basically, i want a program, say broadcast.c, that accepts input from the user and then sends that input to the input of two processes. So if would run this command: ./broadcast prog1 prog2 It would block awaiting the input from the user and then sending that input to prog1 and prog2. Now, i want to use pipes, thing is, i dont know if i have to use 1 pipe or 2 pipes. broadcast.c #include <stdio.h> #include <stdlib.h> #include <unistd.h>

Why doesn't SSH work with a piped password on stdin?

由 旧时模样 提交于 2020-01-04 04:33:07
问题 On a typical Unix system, if I try passing a raw password into SSH through a pipe I will get an error like $ echo password | ssh user@host Pseudo-terminal will not be allocated because stdin is not a terminal. The exact same thing will work with keyboard input which as I understand is provided over stdin in exactly the same manner. I'm not interested in passing a raw password to SSH (this would be terrible for too many reasons to list) I want to understand what's different in this case

前端工程化浅析

由 自闭症网瘾萝莉.ら 提交于 2020-01-04 02:42:29
在过去前端开发一直没有完善的一些代码处理等工具来富足开发，而nodejs火起来之后，很多基于node环境的工具诞生之后对前端开发造成了冲击，慢慢的，使用这些工具来完成项目的搭建和开发这样的方式被称为前端工程化。 使用工程化开发项目原因： 现在的项目不论是规模还是复杂度都有很大程度提高，所以如何快速搭建环境以及搞笑的代码管理，后期处理成为了衡量前端工程师技术的标准 工程化帮我们： 构造环境变得简单、自动化，代码的压缩合并，模块化，抽离都能一步完成，减少了后期处理成本。 现有的工程化工具： grunt、gulp是自动化构建工具，webpack是模块化打包工具，bower、npm是包管理工具 gulp使用方式： 基于流的自动化构建工具。 因为gulp运行在nodejs中，所以遵循commonjs模块化规范，gulp使用通过创建和执行任务来完成 关键方法： 1.gulp.task()创建任务 2.gulp.src()查找资源文件 3.gulp.desk()输出文件 4.gulp.watch(）监听文件内容变化 5. .pipe()可以对文件进行处理 gulp只提供查找、监听文件，处理后输出文件，但是如何处理都不属于gulp的功能范围 工程化的实现： 1、建立项目目录 2、在项目中执行npm init应该有一个package.json文件，标注项目相关信息。 3、选择gulp + gulp

前端工程化讲解

由 佐手、 提交于 2020-01-04 02:41:51
一、什么叫做前端工程化 在过去前端开发一直没有完善的一些代码处理等工具来辅助开发，而nodejs火起来之后，很多基于node环境的工具诞生之后对前端开发造成了冲击，慢慢的，使用这些工具来完成项目的搭建和开发这样的方式被成为前端工程化 二、为什么使用工程化来开发项目 现在的项目不管从规模还是复杂度上都有很大的提高，所以，如何能快速的搭建环境，以及高效的代码管理，后期处理成为了衡量前端工程师技术的一个标准 三、工程化之后能帮助我们做到什么？ 构建环境变得简单和自动化，代码的压缩合并，模块化，抽离都能一步完成，减少了后期处理成本。 四、现有的工程化工具 目前市场上有很多自动化工具供我们选择： grunt、gulp都是自动化构建工具，webpack是模块化打包工具，bower、npm是包管理工具 五、Gulp的使用方式 gulp是一款目前比较流行的基于流的自动化构建工具，因为gulp是运行在nodejs中，所以说也遵循 CommonJS模块化规范，gulp的使用就是通过创建任务和执行任 务来完成 关键方法: 1. gulp.task()创建任务 2. gulp.src()查找资源文件 3. gulp.dest()输出文件 4. gulp.watch()监听文件内容变化 5. .pipe()可以对文件进行处理 gulp提供的只是查找文件，监听文件，处理后输出文件

Why is piping output of subprocess so unreliable with Python?

由 穿精又带淫゛_ 提交于 2020-01-04 01:59:08
问题 (Windows) I wrote some Python code that calls the program SoX (subprocess module), which outputs the progress on STDERR, if you specify it to do so. I want to get the percentage status from the output. If I call it not from the Python script, it starts immediately and has a smooth progression till 100%. If I call it from the Python script, it lasts a few seconds till it starts and then it alternates between slow output and fast output. Although I read char by char sometimes there RUSHES out a

Gradle 'exit' in a shell script

由 女生的网名这么多〃 提交于 2020-01-03 19:17:19
问题 I want to build a package by Gradle (3.2.1) using a script. The script ( hoge.sh ) is #!/bin/sh gradle build echo "hello" ./hoge.sh works and prints "hello". However, cat hoge.sh | /bin/sh -s stops at gradle build . The build looks successful but the process never prints "hello". How can I fix hoge.sh to run by cat hoge.sh | /bin/sh -s correctly?? If I run cat hoge.sh | /bin/sh -i , it returns, sh-4.2$ #!/bin/sh sh-4.2$ gradle build ###gradle information### sh-4.2$ exit For information, using
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