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| 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, split into words as described above
under Word Splitting, and the first word is assigned to the first name, the second word to the second name, and so on. If there are more words than
names, the remaining words and their intervening delimiters are 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 using the same rules the shell uses
for expansion (described above under Word Splitting). 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. If delim is the empty string, read will terminate a line
when it reads a NUL character.
-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 de‐
fault, if line editing was not previously active) editing settings, but uses Readline's default filename completion.
-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 honors a delimiter if fewer than nchars char‐
acters 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.
The result is not split on the characters in IFS; the intent is that the variable is assigned exactly the characters read (with the exception of
backslash; see the -r option below).
-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 then 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 (or a specified number of characters) 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 read times out, read saves any partial input
read into the specified variable name. If timeout is 0, read returns immediately, without trying to read any data. The exit status is 0 if in‐
put is available on the specified file descriptor, non-zero 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, without the ending delimiter but otherwise unmodified, is assigned to the variable REPLY. The exit status is
zero, unless end-of-file is encountered, read times out (in which case the status is greater than 128), a variable assignment error (such as assigning
to a readonly variable) occurs, or an invalid file descriptor is supplied as the argument to -u.
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