我试图得到一个简单的while循环工作在bash使用两个条件，但尝试了许多不同的语法从各种论坛，我不能停止抛出一个错误。这里是我有：
while [ $stats -gt 300 ] -o [ $stats -eq 0 ]
我也试过：
while [[ $stats -gt 300 ] || [ $stats -eq 0 ]]
…以及其他几个结构。我想要这个循环继续，而$ stats是> 300或$ stats = 0。
正确的选项是(按推荐顺序)：
# Single POSIX test command with -o operator (not recommended anymore). # Quotes strongly recommended to guard against empty or undefined variables. while [ "$stats" -gt 300 -o "$stats" -eq 0 ] # Two POSIX test commands joined in a list with ||. # Quotes strongly recommended to guard against empty or undefined variables. while [ "$stats" -gt 300 ] || [ "$stats" -eq 0 ] # Two bash conditional expressions joined in a list with ||. while [[ $stats -gt 300 ]] || [[ $stats -eq 0 ]] # A single bash conditional expression with the || operator. while [[ $stats -gt 300 || $stats -eq 0 ]] # Two bash arithmetic expressions joined in a list with ||. # $ optional,as a string can only be interpreted as a variable while (( stats > 300 )) || (( stats == 0 )) # And finally,a single bash arithmetic expression with the || operator. # $ optional,as a string can only be interpreted as a variable while (( stats > 300 || stats == 0 ))
一些注意事项：
>引用[[…]]和((…)中的参数扩展是可选的;如果未设置变量，-gt和-eq将假定值为0。>使用$是可选内部((…))，但使用它可以帮助避免无意的错误。如果没有设置stats，那么((stats> 300))将假定stats == 0，但是(($ stats> 300))将产生语法错误。
