How to Exit from a Script There are some cases, such as we have written a script to test some code and we need to exit the script in case the code fails, then we can use theexitcommand in the script. A script is terminated with theexitcommand, much like a C program. ...
Putting this at the top of a bash script will cause the script to exit if any commands return a non-zero exit code. We can get a little fancier if we useDEBUGandEXITtrapsto execute custom commands before each line of the script is run and before the script exits, respectively. Adding ...
Running the script demonstrates that the program ends when the variableireaches the value2. Using break Inside a select Loop Theselectcommand creates menus and behaves like an infinite loop, even though it's not one of the primary loop constructs. To exit theselectstatement elegantly, make a ca...
The simplest way to make a bash script exit when an error occurs is by using the'set -e'command at the beginning of your bash script. This command instructs the bash script to stop execution if any command it runs returns a non-zero exit status, which is the convention for indicating ...
exit # exit script fi echo keep running ~/bin/process_data # do some work done 如果要退出循环而不是退出脚本,请使用break命令而不是exit。 #!/bin/bash while true do if [ `date +%H` -ge 17 ]; then break # exit loop fi echo keep running ...
followed by the path to the shell, in this case bash - this acts as an interpreter directive and ensures that the script is executed under the correct shell.The "#" character indicates a comment, so the shebang line is ignored by bash when running the script.Next...
To avoid future surprises, the bulk of the code should typically not be the subshell. This is all right:while read -r i; do printf '%s\n' "$i" done < <(seq 1 10) How to begin a bash scripthashbang#!/usr/bin/env bash Portability consideration: The absolute path to env is ...
exit The slightly strange "fi" keyword ("if" reversed) signals the end of an if statement in Bash: fi Your script can now continue as before, to handle the case when an argument is present: mkdir$1 When you run this new version of the script, you’ll get a message if you forget ...
$ ./myscript 'arg 1' arg2 arg3 parameter: 'arg 1' parameter: 'arg2' parameter: 'arg3' 上面正确的例子中,第一个参数 'arg 1' 在展开后依然是一个独立的单词,而不会被拆分成两个。 25. function foo() 这种写法不一定能够兼容所有 shell,兼容的写法是: ...
If a shell script runs into problems during its execution, resulting in an error signal that interrupts the script unexpectedly it may leave behind temporary files that cause trouble when a user restarts the script. UsingBash trap Command, you can ensure your scripts always exit predictably....