在Linux中，您可以使用test命令或方括号[]来检测环境变量
test命令：if test "$VARIABLE" = "value"; then
echo "Environment variable is set and has the expected value."
else
echo "Environment variable is not set or has a different value."
fi
[]：if [ "$VARIABLE" = "value" ]; then
echo "Environment variable is set and has the expected value."
else
echo "Environment variable is not set or has a different value."
fi
请将VARIABLE替换为您要检查的环境变量名称，将value替换为预期的环境变量值。注意，我们在变量和值周围使用了双引号，以防止空格或其他特殊字符引起的问题。
