shell script if file exists

I. Logical judgments in shell scriptsIn the shell script, many will logically judge, judge a certain value, judge a file, or a directory, we do some action against the result of the judgment, if there is no judgment, there is no way to do some

Use shell script to monitor whether a process exists without a startup instance, first on the code dry: #!/bin/sh ps-fe|grep processstring |grep-v grep if [$-ne 0] then echo "START process ..." elseecho "runing ..." fi

1. What is a shell script?It is a scripting language, not a programming language.You can use some logical judgments, loops, and other syntax.You can customize the sub-function, which is a collection of system commands.Shell scripts enable automated

#!/bin/shPs-fe|grep processstring |grep-v grepIf [$?-ne 0]Thenecho "START process ..."Elseecho "Runing ..."Fi#####Processstring represents a process feature string that can be queried for a unique process's characteristic string0 indicates the

Shell script programming and file system RepairGuideThe Linux Foundation has initiated the LFCS certification (Linux Foundation Certification System Administrator) Linux Foundation Certified Sysadmin, which is a brand new certification system, the

Use shell script to monitor whether a process exists without a startup instance, first on the code dry: #!/bin/shPs-fe|grep processstring |grep-v grepIf [$?-ne 0]Thenecho "START process ..."Elseecho "Runing ..."Fi#####Processstring represents a

Shell programming BASICS (from the UBUNTU Forum) (12:49:20) Reprinted Tags:Shell Classification: programming (C ++) Http://wiki.ubuntu.org.cn/Shell%E7%BC%96%E7%A8%8B%E5%9F%BA%E7%A1%80 Why shell programming?In Linux, although there

Using a shell to determine whether a device node exists, such as inserting a 4G Modem Sierra module into a Linux system, generates a series of TTY devices, typically with a command to send and receive at. For example, a device node is a/DEV/TTYUSB2

Common shell: -------------- from "laruence's Linux private dish" In the early UNIX era, there were many developers, so shell had many versions based on the developer's differences, such Frequently heard Bourne shell (SH ),C shell,Commonly used

Create a scriptThere are many different shells in Linux, but usually we use Bash (Bourne again shell) for Shell programming because bash is free and easy to use. So the script I've provided in this article is all about using bash (but in most cases