Use Node. js to compile cross-platform spawn statements.
Preface
Node. js is cross-platform, that is, it can run on Windows, OSX, and Linux platforms. Many Node. js developers develop code on OSX and then deploy the code on the Linux server. Because OSX and Linux are both Unix-based, they have many commonalities. Windows is also officially supported by Node. js. As long as you write code in the correct way, you can run it without any pressure on each platform.
Node. js sub-processes (child_process
)spawn
Functions can be used to call system commands, such as Linux and macOS.
const spawn = require('child_process').spawn;spawn('npm', { stdio: 'inherit'});
To callnpm
Command.
However, if the same statement is executed on Windows, an error is reported.
Error: spawn npm ENOENT at exports._errnoException (util.js:855:11) at Process.ChildProcess._handle.onexit (internal/child_process.js:178:32) at onErrorNT (internal/child_process.js:344:16) at nextTickCallbackWith2Args (node.js:455:9) at process._tickCallback (node.js:369:17) at Function.Module.runMain (module.js:432:11) at startup (node.js:141:18) at node.js:980:3
Because in Windows, when we run npm, what we actually execute isnpm.cmd
Batch Processing, while on Windows,.cmd
,.bat
Batch Processing cannot be separatedcmd.exe
This interpreter runs independently.
Therefore, we need to explicitly call cmd
spawn('cmd', ['/c', 'npm'], { stdio: 'inherit'});
Or usespawn
Setshell
Option:true
To callcmd
(This option is added from Node. js v6)
spawn('npm', { stdio: 'inherit', shell: true});
In addition, you do not need to setshell
Option, the command can also be executed normally; Setshell
Istrue
It will not impede command execution, but will generate an additional unnecessary shell process, affecting the performance.
Therefore, if you want to write cross-platformspawn
Command, but do not want to add additional overhead, you can write
Const process = require ('process'); const {spawn} = require ('child _ Process'); spawn ('npm ', {stdio: 'herit ', // use shell: process only when the current running environment is Windows. platform = 'win32 '});
Third-party Module cross-spawn
Aboutspawn
Function cross-platform writing, in addition to processing code by yourself, there are also third-party modules that encapsulate relevant details, such as cross-spawn.
This module can be calledspawn
The function automatically determines whether to generateshell
To execute the given command.
In addition
- Node. js versions earlier than v6 are supported (Use
shell
Option requires at least Node. js v6 );
- Cross-platform support for shebang;
- It is more convenient to escape characters in commands and parameters.
Install
npm install cross-spawn
Usage
const spawn = require('cross-spawn');spawn('npm', { stdio: 'inherit'});
References
Export the. bat and. cmd files on Windows
Summary
The above is all about this article. I hope this article will help you in your study or work. If you have any questions, please leave a message.