read

Read a line from the standard input and split it into fields.

Documentation

• read [EN] @ GNU Bash Reference Manual

• bash -c 'help read'
• man 1 'bash' [EN]

Syntax

read [PARAMETER ...] [NAME ...]

Parameters

-a ARRAY

Assign the words read to sequential indices of the array variable ARRAY.

-d DELIMITER

Continue until the first character of DELIMITER is read, rather than newline.

-e

Use Readline to obtain the line in an interactive shell.

-N NUMBER

Return only after reading exactly NUMBER of 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 TIME

Time out and return failure if a complete line of input is not read within TIME seconds. The value of the TMOUT variable is the default timeout. TIME may be a fractional number. If TIME 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.

Examples

Get a password

read -p 'Password: ' -r -s password

Get a yes or no answer

read -N 1 -p 'Y or N: ' -r answer

Read each field of a file

while IFS=':' read -r user passwd uid gid info home shell; do
   echo "User:     ${user}"
   echo "User ID:  ${uid}"
   echo "Group ID: ${gid}"
   echo "Info:     ${info}"
   echo "Home Dir: ${home}"
   echo "Shell:    ${shell}"
   echo
done <'/etc/passwd'

Provide an opportunity to leave the script

read -n 1 -p 'Press Ctrl-C to exit or any key to proceed.' -r -s