有人能告诉我以下shell命令的作用吗?
if ! mkdir -p $APPLICATION_DIRECTORY/conf
答案 0 :(得分:4)
mkdir -p "$APPLICATION_DIRECTORY/conf"
尝试创建命名目录,沿途创建任何缺少的父目录。与每个命令一样,它具有整数退出状态,其中0表示目录已成功创建,非零值表示某种错误。
if
命令测试其命令的退出状态,而不是大多数其他编程语言中的布尔值。 !
运算符取消退出状态:非零退出状态转换为0,退出状态0转换为1.
换句话说,
if ! mkdir -p "$APPLICATION_DIRECTORY/conf"; then
echo "There was an error creating the directory"
else
echo "The directory was successfully created"
fi
答案 1 :(得分:0)
你也可以使用直接逻辑(更容易理解):如果mkdir -p ...
示例:
if mkdir -p "$APPLICATION_DIRECTORY/conf"; then
echo "The directory was successfully created"
else
echo "There was an error creating the directory"
fi