For details about the/dev/null and/dev/zero files, and solutions for accidental deletion of/dev/null and/dev/zero, and the disk I/O Testing Method Using/dev/zero, disk deletion and recovery by mistake1. Introduction-explanation from
1, Introduction--From the wiki interpretation/dev/null:In a Unix-like system, a/dev/null, or empty device, is a special device file that discards everything written to it (but reports a successful write operation) and reads it immediately to get an
Detailed description of/dev/null and/dev/zero files, solutions for accidental deletion of/dev/null and/dev/zero, and disk I/O testing using/dev/zero1. Introduction-explanation from Wikipedia/dev/null:
In Unix-like systems,/dev/null, or an empty
Linux is a file-based system, and all hardware, such as software, will have a corresponding file representation under the directory. For Dev This directory, we know the file below it, which represents the Linux device. In Windows systems, devices
Linux is a file system, and all hardware, such as software, will be represented under the appropriate directory. For the dev directory, we know that the file below it represents the Linux device. In Windows, devices are well understood, like hard
Using/dev/null
Think of/dev/null as a "black hole". It is very equivalent to a write-only file. All content written to it is lost forever. And trying to read content from it is nothing. However,/dev/null is very useful for both the command line and
In a Unix-like system,/dev/null is called an empty device, which is a special device file that discards everything written to it, but he reports that the write succeeds and reads it immediately to get an EOF. In programmer jargon, especially in Unix
The difference between/dev/null and/dev/zero/dev/null, nicknamed the Bottomless pit, you can output any data to it, it take all, and will not hold!/dev/zero, is an input device that you can use to initialize files. The device provides an exhaustive 0
Use
/Dev/null
Set/Dev/nullIt is regarded as a "black hole". It is very equivalent to a write-only file. All the content written to it will be lost forever. However, if you try to read the content from it, nothing can be read.
False, zero, null, undefined, and empty string objects in Javascript
In Javascript, We often come into contact with the five special objects mentioned in the question -- false, 0, empty string, NullAnd undefined. These objects are easy to use
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