Shell Programming and Scripting

       read [-ers] [-a aname] [-d delim] [-i text] [-n nchars] [-N nchars] [-p prompt] [-t timeout] [-u fd] [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.  Readline uses the current (or default, if line editing was not previously active) editing settings.
              -i text
                     If readline is being used to read the line, text is placed into the editing buffer before editing begins.
              -n nchars
                     read returns after reading nchars characters rather than waiting for a complete line of input, but honor a delimiter if fewer than nchars characters are read before the delimiter.
              -N nchars
                     read  returns after reading exactly nchars characters rather than waiting for a complete line of input, unless EOF is encountered or read times out.  Delimiter characters encountered in the input are not treated
                     specially and do not cause read to return until nchars characters are read.
              -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.  timeout may be a decimal number with a fractional portion following the decimal point.  This  option  is
                     only  effective if read is reading input from a terminal, pipe, or other special file; it has no effect when reading from regular files.  If timeout is 0, read returns success if input is available on the speci‐
                     fied file descriptor, failure otherwise.  The exit status is greater than 128 if the timeout is exceeded.
              -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 (in which case the return code is greater than 128), or an  invalid
              file descriptor is supplied as the argument to -u.

read -n 1 -t 5 -p "Type your answer " input

TMOUT=60 read input