shell,python,perl（面向过程） 面向对象：shell，
$mkdirusers2>errors.txt $caterrors.txt mkdir: cannot create directory ‘users’: File exists Most of the time, it is difficult to find the exact line number in scripts. To print the line number with the error, use thePS4option (supported with Bash 4.1 or later). Example below: ...
bash脚本退出代码解释 Exit Codes With Special Meanings Table E-1.ReservedExit Codes According to the above table, exit codes1 - 2, 126 - 165, and 255[1]have special meanings, and should therefore be avoided for user-specified exit parameters. Ending a script withexit 127would certainly cause...
echo 'Must supply a parameter, exiting.' >&2 exit 1 ;; *) echo 'Unknown error, exiting.' >&2 exit $status esac
Create a Bash file with the following script that shows the use of the Bash error handling by exit status code. Any Bash command is taken as input value and that command is executed later. If the exit status code is not equal to zero, an error message is printed. Otherwise, a success...
在使用 break 时需要注意的是,它与 return 及 exit 是不同的:*break 是结束 loop* return 是结束function* exit 是结束 script/shell 而continue 则与 break 相反:强迫进入下一次循环动作。若你理解不来的话,那你可简单的看成:在 continue 到done之间的句子略过而返回循环顶端...与 break 相同的是:continue...
echo "$instances instance(s) of this script running." echo "[Hit Ctl-C to exit.]"; echo sleep 1 # 等一下. bash $0 # 再来一次, Sam. exit 0 # 没必要; 脚本永远不会运行到这里. # 为什么运行不到这里? # 在使用Ctl-C退出之后, ...
Bash Script Returns with Different Return Codes on Exit Before moving out to the methods, let’s take a look at the exit codes that have specific meanings: How to Get Return Codes on Exit? You only need to write the “echo $?” command to get the return code. For example, you want...
If the error is unrecoverable and you want to exit the script, choose this. This will give you the same effect as set -e, exiting at the error.echo Many long and complex actions false echo Many more long and complex actionsNote it exited after false, and the final echo statement never...
The if in a Bash script is a shell keyword that is used to test conditions based on the exit status of a test command. An exit status of zero, and only zero, is a success, i.e. a condition that is true. Any other exit status is a failure, i.e. a condition that is false. ...