shell脚本中if判断时候-s是什么意思-s file ⽂件⼤⼩⾮0时为真
[ -f "somefile" ] ：判断是否是⼀个⽂件
房子风水
[ -x "/bin/ls" ] ：判断/bin/ls是否存在并有可执⾏权限
[ -n "$var" ] ：判断$var变量是否有值
[ "$a" = "$b" ] ：判断$a和$b是否相等
-r file ⽤户可读为真
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-w file ⽤户可写为真
安全手抄报简单-x file ⽤户可执⾏为真
-f file ⽂件为正规⽂件为真
-d file ⽂件为⽬录为真
-c file ⽂件为字符特殊⽂件为真
-
b file ⽂件为块特殊⽂件为真方大洪
-s file ⽂件⼤⼩⾮0时为真 -s file true if the file has nonzero size
-t file 当⽂件描述符(默认为1)指定的设备为终端时为真
-a file exists.
-b file exists and is a block special file.
-c file exists and is a character special file.
-d file exists and is a directory.
-e file exists (just the same as -a).
一年级元宵节手抄报-f file exists and is a regular file.
-g file exists and has its tgid(2) bit t.
马邑之战-G file exists and has the same group ID as this process.
-
k file exists and has its sticky bit t.
面筋的做法
-L file exists and is a symbolic link.
香港百佳超市-n string length is not zero.
-o Named option is t on.
-O file exists and is owned by the ur ID of this process.
-p file exists and is a first in, first out (FIFO) special file or
named pipe.
-r file exists and is readable by the current process.
-s file exists and has a size greater than zero.
-S file exists and is a socket.
-t file descriptor number fildes is open and associated with a
terminal device.
-u file exists and has its tuid(2) bit t.
-w file exists and is writable by the current process.
-x file exists and is executable by the current process.
-z string length is zero.
