bash if file not exist

Basic syntax for BASH The simplest example of--hello world! About input, output, and error outputs Rules for variables in BASH (similarities and differences with C language) Basic Process Control syntax in BASH Use of

Basic syntax for BASH The simplest example of--hello world! About input, output, and error outputs Rules for variables in BASH (similarities and differences with C language) Basic Process Control syntax in BASH Use of

The simplest example of--hello world! About input, output, and error outputs Rules for variables in BASH (similarities and differences with C language) Basic Process Control syntax in BASH Use of functions 2.1 Simplest example

https://www.zhihu.com/question/21418449Mort | Zsh vs. Bash: Incomplete contrast resolution (1) 2014-10-07BdpqlxzWhat's the difference between zsh and bash?A lot of people have written about "why zsh is better than bash", "Why zsh is better than

Shell commonly known as shell (used to distinguish from the kernel), refers to the "user interface to provide users" command parser (software). It is similar to DOS command and later cmd.exe. It receives the user command and then invokes the

Understanding of the Bash environment variable Parsing Vulnerability 1. What are environment variables?Both Windows and Linux programs support environment variables. Generally, environment variables are stored at the beginning of the process memory

First, compile bash to implement the syslog logging function of Bash 1. This paper will realize the function of history record to syslog log through bash software, and it can be transferred to the remote log centralized server in real-time, which

Some basic Bash ProblemsSome basic Bash ProblemsHere we will introduce some issues before and after bash is started, as well as some basic issues that need to be paid attention to when using bash.1. Bash IntroductionBash is a Shell program. It is

Let's take a look at the simple technique for processing command line independent variables, and then look at the basic programming structure of bash. Receive independent variable In the sample program in the introductory article, we use the

1. Linux Scripting Basics 1.1 Basic Introduction to grammar 1.1.1 Start The program must start with the following line (must be on the first line of the file): #!/bin/sh The symbolic #! is used to tell the system that the parameters behind it