read [-ers] [-u fd] [-t timeout] [-a aname] [-p prompt] [-n nchars] [-d delim] [name ...]
One line is read from the standard input, or from the file descriptor fd supplied as an argument to the -u option, and the
first word is assigned to the first name, the second word to the second name, and so on, with leftover words and their
intervening separators assigned to the last name. If there are fewer words read from the input stream than names, the
remaining names are assigned empty values. The characters in IFS are used to split the line into words. The backslash
character (\) may be used to remove any special meaning for the next character read and for line continuation. Options,
if supplied, have the following meanings:
-a aname
The words are assigned to sequential indices of the array variable aname, starting at 0. aname is unset before any
new values are assigned. Other name arguments are ignored.
-d delim
The first character of delim is used to terminate the input line, rather than newline.
-e If the standard input is coming from a terminal, readline (see READLINE above) is used to obtain the line.
-n nchars
read returns after reading nchars characters rather than waiting for a complete line of input.
-p prompt
Display prompt on standard error, without a trailing newline, before attempting to read any input. The prompt is
displayed only if input is coming from a terminal.
-r Backslash does not act as an escape character. The backslash is considered to be part of the line. In particular,
a backslash-newline pair may not be used as a line continuation.
-s Silent mode. If input is coming from a terminal, characters are not echoed.
-t timeout
Cause read to time out and return failure if a complete line of input is not read within timeout seconds. This
option has no effect if read is not reading input from the terminal or a pipe.
-u fd Read input from file descriptor fd.
If no names are supplied, the line read is assigned to the variable REPLY. 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.