bash - How to enable the up/down arrow keys to show previous inputs when using `read`? -

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i'm waiting user input (using 'read') in infinite loop , have command history, being able show previous inputs entered, using , down arrow keys, instead of getting ^[[a , ^[[b. possible?

thanks @l0b0 answer. got me on right direction. after playing time i've realized need following 2 features, haven't managed them yet:

  • if press , add previous command have whole thing saved in history, not addition. example

    $ ./up_and_down
    enter command: hello
    enter
    enter command:
    up
    enter command: hello you
    enter
    enter command:
    up
    enter command: you
    (instead of "hello you")

  • if can't keep going because i'm @ end of history array, don't want cursor move previous line, instead want stay fixed.

this have far (up_and_down):

#!/usr/bin/env bash set -o nounset -o errexit -o pipefail  read_history() {     local char     local string     local esc=$'\e'     local up=$'\e[a'     local down=$'\e[b'     local clear_line=$'\r\e[k'       local history=()     local -i history_index=0      # read 1 character @ time     while ifs="" read -p "enter command:" -n1 -s char ;         if [[ "$char" == "$esc" ]];              # rest of escape sequence (3 characters total)             while read -n2 -s rest ;                 char+="$rest"                 break             done         fi          if [[ "$char" == "$up" && $history_index > 0 ]] ;             history_index+=-1             echo -ne $clear_line${history[$history_index]}         elif [[ "$char" == "$down" && $history_index < $((${#history[@]} - 1)) ]] ;             history_index+=1             echo -ne $clear_line${history[$history_index]}         elif [[ -z "$char" ]]; # user pressed enter             echo             history+=( "$string" )             string=             history_index=${#history[@]}         else             echo -n "$char"             string+="$char"         fi     done } read_history

two solutions using -e option read command combined builtin history command:

# version 1 while ifs="" read -r -e -d $'\n' -p 'input> ' line;     echo "$line"    history -s "$line" done  # version 2 while ifs="" read -r -e -d $'\n' -p 'input> ' line;     echo "$line"    echo "$line" >> ~/.bash_history    history -n done

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