= STRIN2 # Trueifstrings arenotequal#算术测试操作var1 -eq var2 # Trueifvar1 is equal to var2var1 -ne var2 # Trueifvar1notequal to var2var1 -lt var2 # Trueifvar1 is less than var2var1 -le var2 # Trueifvar1 is less thanorequal ...
This way, to test if a number, n, is prime for numbers greater than 3, we perform a series of steps: check if n is divisible by 2 or 3 check if n is divisible by numbers of the form 6k-1 or 6k+1 that are less than or equal to the square root of n If n satisfies neither...
/bin/bash # Calculate the week number using the date command: WEEKOFFSET=$[ $(date +"%V") % 2 ] # Test if we have a remainder. If not, this is an even week so send a message. # Else, do nothing. if [ $WEEKOFFSET -eq "0" ]; then echo "Sunday evening, put out the gar...
printf "Enter a number between 10 and 20 inclusive: " read number if (( number < 10 )) then printf "%d is too low\n" "$number" >&2 exit 1 elif (( number > 20 )) then printf "%d is too high\n" "$number" >&2 exit 1 else printf "You entered %d\n" "$number" fi 注...
if [ -z ${var+x} ]; then echo "var is unset"; else echo "var is set to '$var'"; fi 参考:https://stackoverflow.com/questions/3601515/how-to-check-if-a-variable-is-set-in-bash 6、换算秒为分钟、小时 代码语言:javascript 代码运行次数:0 运行 AI代码解释 #!/bin/bash a=60100 sw...
check-scripts:# Fail if any of these files have warningsshellcheck myscripts/*.sh or in a Travis CI.travis.ymlfile: script:# Fail if any of these files have warnings-shellcheckmyscripts/*.sh Services and platforms that have ShellCheck pre-installed and ready to use: ...
在Bash/Shell脚本中,可以使用特殊字符"\n"来表示换行符。当需要在变量中插入换行符时,可以使用以下方法: 1. 使用双引号(")包裹字符串,并在需要插入换行符的位置使用"\n"。例如: `...
Afterdeclaring a string variable, use the-zoperator in anif statementto check whether a string is empty or not: MY_STRING="" if [ -z $MYSTRING ] then echo "String is empty" else echo "String is not empty" fi For more Shell scripting tips,check out or Bash/Shell scripting articles!
anny ~> ./msgcheck.sh This scripts checks the existence of the messages file. Checking... /var/log/messages exists. ...done. 7.1.1.4. 检查shell选项 加入到你的Bash配置文件中去: # These lines will print a message if the noclobber option is set: if [ -o noclobber ] then echo "Your...
# line number. echo"Example of error with line number and message" error_exit"$LINENO: An error has occurred." 在bash脚本中有更好的错误处理例程吗? 相关讨论 请参阅这个详细的答案:在bash脚本中引发错误。 请参阅以下日志记录和错误处理实现:github.com/codeforester/base/blob/master/lib/stdlib.sh ...