Bash脚本，请解释这个语法 读取dir-ev文件时；做 #做事 完成

我找不到解释的部分是

readdirev

部分。我不熟悉Bash。我主要做PHP和MySQL。有人能解释一下吗

---

谢谢。

简短的版本是，它一次从输入中取出一行，并将其中的各个字段分配到变量中

read dir ev file

将一行一行地读取，并期望每行包含3项。然后，它将第一个项目分配到名为

dir

的变量中，第二个项目分配到名为

ev

的变量中，第三个项目分配到名为

file

的变量中

---

从

帮助的输出中读取

：

（编辑：此处有更可读的版本：）

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在shell中说“帮助阅读”。谢谢。我在查看

的同时

没有想到查看

阅读

注意“为姓氏分配了任何剩余单词”的注释。如果行上有6个字段，则前两个字段分配给

dir

和

ev

，其余字段位于

文件中。如果只有两个字段，则
文件
为空；如果只有一个字段，那么
ev
和
file
为空。@Amber谢谢，太棒了。我不知道发生了什么事。从其他地方复制while循环的内容，认为
ev
是某种保留字。
read: read [-ers] [-a array] [-d delim] [-i text] [-n nchars] [-N nchars] [-p prompt] [-t timeout] [-u fd] [name ...]
    Read a line from the standard input and split it into fields.

    Reads a single line from the standard input, or from file descriptor FD
    if the -u option is supplied.  The line is split into fields as with word
    splitting, and the first word is assigned to the first NAME, the second
    word to the second NAME, and so on, with any leftover words assigned to
    the last NAME.  Only the characters found in $IFS are recognized as word
    delimiters.

    If no NAMEs are supplied, the line read is stored in the REPLY variable.

    Options:
      -a array  assign the words read to sequential indices of the array
                variable ARRAY, starting at zero
      -d delim  continue until the first character of DELIM is read, rather
                than newline
      -e                use Readline to obtain the line in an interactive shell
      -i text   Use TEXT as the initial text for Readline
      -n nchars return after reading NCHARS characters rather than waiting
                for a newline, but honor a delimiter if fewer than NCHARS
                characters are read before the delimiter
      -N nchars return only after reading exactly NCHARS characters, unless
                EOF is encountered or read times out, ignoring any delimiter
      -p prompt output the string PROMPT without a trailing newline before
                attempting to read
      -r                do not allow backslashes to escape any characters
      -s                do not echo input coming from a terminal
      -t timeout        time out and return failure if a complete line of input is
                not read withint TIMEOUT seconds.  The value of the TMOUT
                variable is the default timeout.  TIMEOUT may be a
                fractional number.  If TIMEOUT is 0, read returns success only
                if input is available on the specified file descriptor.  The
                exit status is greater than 128 if the timeout is exceeded
      -u fd             read from file descriptor FD instead of the standard input

    Exit Status:
    The return code is zero, unless end-of-file is encountered, read times out,
    or an invalid file descriptor is supplied as the argument to -u.