Reading Function Keys in bash
This is sample code to allow more intuitive usage of Function keys in bash. It abstracts the escape sequence messiness for these keys and as such allows for a more portable/intuitive solutions.
#set -o errexit
#set -o errtrace
set -o nounset
if [ "${S8C1T:-0}" != "1" ] ; then
declare -gr SS3=$'\eO' # Single Shift Select of G3 Character Set ( SS3 is 0x8f): affects next character only
declare -gr CSI=$'\e[' # Control Sequence Introducer ( CSI is 0x9b)
else
declare -gr SS3=$'\x8f' # Single Shift Select of G3 Character Set ( SS3 is 0x8f): affects next character only
declare -gr CSI=$'\x9b' # Control Sequence Introducer ( CSI is 0x9b)
fi
function vt100_DECRST {
IFS=';' eval 'echo -n "${CSI}?${*?Missing Pm}l"'
}
function vt100_DECSET {
IFS=';' eval 'echo -n "${CSI}?${*?Missing Pm}h"'
}
mouse_type=(
[0]=9 ## X10 mouse reporting, for compatibility with X10's xterm, reports on button press.
[1]=1000 ## X11 mouse reporting, reports on button press and release.
[2]=1001 ## highlight reporting, useful for reporting mouse highlights
[3]=1002 ## button movement reporting, reports movement when a button is presse
[4]=1003 ## all movement reporting, reports all movements.
[5]=1004 ## FocusIn/FocusOut can be combined with any of the mouse events since it uses a different protocol. When set, it causes xterm to send CSI I when the terminal gains focus, and CSI O when it loses focus.
[6]=1005 ## Extended mouse mode enables UTF-8 encoding for C x and C y under all tracking modes, expanding the maximum encodable position from 223 to 2015. For positions less than 95, the resulting output is identical under both modes. Under extended mouse mode, positions greater than 95 generate "extra" bytes which will confuse applications which do not treat their input as a UTF-8 stream. Likewise, C b will be UTF-8 encoded, to reduce confusion with wheel mouse events.
)
function ord {
printf -v "${1?Missing Dest Variable}" "${3:-%d}" "'${2?Missing Char}"
}
function ord_eascii {
LC_CTYPE=C ord "${@}"
}
function AdjustMousePos {
local -i _INDEX
ord_eascii _INDEX "${2}"
eval ${1}'=$(( ${_INDEX}-32))'
}
###############################
##
## READ KEY CRAP
##
##
###############################
KeyModifiers=(
[2]="S" [3]="A" [4]="AS" [5]="C" [6]="CS" [7]="CA" [8]="CAS"
[9]="M" [10]="MS" [11]="MA" [12]="MAS" [13]="MC" [14]="MCS" [15]="MCA" [16]="MCAS"
)
KeybFntKeys=(
[1]="home" [2]="insert" [3]="delete" [4]="end" [5]="pageUp" [6]="pageDown"
[11]="f1" [12]="f2" [13]="f3" [14]="f4" [15]="f5"
[17]="f6" [18]="f7" [19]="f8" [20]="f9" [21]="f10"
[23]="f11" [24]="f12" [25]="f13" [26]="f14" [28]="f15"
[29]="f16" [31]="f17" [32]="f18" [33]="f19" [34]="f20"
)
SunKeybFntKeys=(
[214]="home" [2]="insert" [3]="delete" [4]="end" [216]="pageUp" [222]="pageDown"
[224]="f1" [225]="f2" [226]="f3" [227]="f4" [228]="f5"
[229]="f6" [230]="f7" [231]="f8" [232]="f9" [233]="f10"
[192]="f11" [193]="f12" [218]="keypad-five" [220]="keypad-delete"
)
KeybFntKeysAlt=(
# A B C D E F H
[0x41]="up" [0x42]="down" [0x43]="right" [0x44]="left" [0x45]="keypad-five" [0x46]="end" [0x48]="home"
# I O
[0x49]="InFocus" [0x4f]="OutOfFocus"
# P Q R S Z
[0x50]="f1" [0x51]="f2" [0x52]="f3" [0x53]="f4" [0x5a]="S-HT"
)
C0CtrlChars=(
[0x00]="Null" [0x01]="SOH" [0x02]="STX" [0x03]="ETX" [0x04]="EOT" [0x05]="ENQ" [0x06]="ACK"
[0x07]="BEL" [0x08]="BS" [0x09]="HT" [0x0A]="LF" [0x0B]="VT" [0x0C]="FF" [0x0D]="CR"
[0x0E]="SO" [0x0F]="SI" [0x10]="DLE" [0x11]="DC1" [0x12]="DC2" [0x13]="DC3" [0x14]="DC4"
[0x15]="NAK" [0x16]="SYN" [0x17]="ETB" [0x18]="CAN" [0x19]="EM" [0x1A]="SUB" [0x1B]="ESC"
[0x1C]="FS" [0x1D]="GS" [0x1E]="RS" [0x1F]="US" [0x20]="SP" [0x7F]="DEL"
)
C0CtrlCharsAlt=(
[0x01]="C-A" [0x02]="C-B" [0x03]="C-C" [0x04]="C-D" [0x05]="C-E" [0x06]="C-F" [0x07]="C-G"
[0x08]="C-H" [0x09]="C-I" [0x0a]="C-J" [0x0b]="C-K" [0x0c]="C-L" [0x0d]="C-M" [0x0e]="C-N"
[0x0f]="C-O" [0x10]="C-P" [0x11]="C-Q" [0x12]="C-R" [0x13]="C-S" [0x14]="C-T" [0x15]="C-U"
[0x16]="C-V" [0x17]="C-W" [0x18]="C-X" [0x19]="C-Y" [0x1a]="C-Z" [0x1b]="C-[" [0x1c]="C-]"
[0x1d]="C-}" [0x1e]="C-^" [0x1f]="C-_" [0x20]="C-SP" [0x7F]="DEL"
)
C1CtrlCharsEsc=(
[0x40]="PAD" [0x41]="HOP" [0x42]="BPH" [0x43]="NBH"
[0x44]="IND" [0x45]="NEL" [0x46]="SSA" [0x47]="ESA"
[0x48]="HTS" [0x49]="HTJ" [0x4A]="VTS" [0x4B]="PLD"
[0x4C]="PLU" [0x4D]="RI" [0x4E]="SS2" [0x4F]="SS3"
[0x50]="DCS" [0x51]="PU1" [0x52]="PU2" [0x53]="STS"
[0x54]="CCH" [0x55]="MW" [0x56]="SPA" [0x57]="EPA"
[0x58]="SOS" [0x59]="SGCI" [0x5A]="SCI" [0x5B]="CSI"
[0x5C]="ST" [0x5D]="OSC" [0x5E]="PM" [0x5F]="APC"
)
C1CtrlChars=(
[0x80]="PAD" [0x81]="HOP" [0x82]="BPH" [0x83]="NBH"
[0x84]="IND" [0x85]="NEL" [0x86]="SSA" [0x87]="ESA"
[0x88]="HTS" [0x89]="HTJ" [0x8A]="VTS" [0x8B]="PLD"
[0x8C]="PLU" [0x8D]="RI" [0x8E]="SS2" [0x8F]="SS3"
[0x90]="DCS" [0x91]="PU1" [0x92]="PU2" [0x93]="STS"
[0x94]="CCH" [0x95]="MW" [0x96]="SPA" [0x97]="EPA"
[0x98]="SOS" [0x99]="SGCI" [0x9A]="SCI" [0x9B]="CSI"
[0x9C]="ST" [0x9D]="OSC" [0x9E]="PM" [0x9F]="APC"
)
C1CtrlCharsAlt=(
[0x01]="CA-A" [0x02]="CA-B" [0x03]="CA-C" [0x04]="CA-D" [0x05]="CA-E" [0x06]="CA-F" [0x07]="CA-G"
[0x08]="CA-H" [0x09]="CA-I" [0x0a]="CA-J" [0x0b]="CA-K" [0x0c]="CA-L" [0x0d]="CA-M" [0x0e]="CA-N"
[0x0f]="CA-O" [0x10]="CA-P" [0x11]="CA-Q" [0x12]="CA-R" [0x13]="CA-S" [0x14]="CA-T" [0x15]="CA-U"
[0x16]="CA-V" [0x17]="CA-W" [0x18]="CA-X" [0x19]="CA-Y" [0x1a]="CA-Z" [0x1b]="CA-[" [0x1c]="CA-]"
[0x1d]="CA-}" [0x1e]="CA-^" [0x1f]="CA-_" [0x20]="CA-SP" [0x7F]="A-DEL"
)
MouseButtons=(
[0x00]="MB1-P" [0x01]="MB2-P" [0x02]="MB3-P" [0x03]="MB-R"
[0x20]="MB1-M" [0x21]="MB2-M" [0x22]="MB3-M" [0x23]="MB-M"
[0x40]="MB4-P" [0x41]="MB5-P"
)
MouseMetaButtons=(
[0x04]="S-" [0x08]="A-" [0x0c]="AS-"
[0x10]="C-" [0x14]="CS-" [0x1c]="CAS-"
)
function GetMouseButton {
local MouseBtn
AdjustMousePos MouseBtn "${2}"
MouseBtn="${MouseMetaButtons[$(( ${MouseBtn} & 0x1C))]-}${MouseButtons[$(( ${MouseBtn} & 0xe3))]}"
eval ${1}='"${MouseBtn}"'
}
mouse_on="$(vt100_DECSET ${mouse_type[1]})"
mouse_off="$(vt100_DECRST "${mouse_type[1]}" )"
function ReadKey {
unset UInput[@]
local escapeSequence
local REPLY
echo -n "${mouse_on}"
if IFS='' read -srN1 ${1:-} escapeSequence; then
case "${escapeSequence}" in
[^[:cntrl:]])
UInput[0]="${escapeSequence}"
;;
$'\e')
while IFS='' read -srN1 -t0.0001 ; do
escapeSequence+="${REPLY}"
done
case "${escapeSequence}" in
$'\e'[^[:cntrl:]]) echo -n "A-${escapeSequence:1}" ;;
${CSI}t)
UInput[0]="MouseTrack"
AdjustMousePos UInput[1] "${escapeSequence:3:1}"
AdjustMousePos UInput[2] "${escapeSequence:4:1}"
;;
${CSI}T)
UInput[0]="MouseTrack"
AdjustMousePos UInput[1] "${escapeSequence:3:1}"
AdjustMousePos UInput[2] "${escapeSequence:4:1}"
AdjustMousePos UInput[3] "${escapeSequence:5:1}"
AdjustMousePos UInput[4] "${escapeSequence:6:1}"
AdjustMousePos UInput[5] "${escapeSequence:7:1}"
AdjustMousePos UInput[6] "${escapeSequence:8:1}"
;;
${CSI}M*)
GetMouseButton UInput[0] "${escapeSequence:3:1}"
if [ -n "${UInput[0]}" ]; then
AdjustMousePos UInput[1] "${escapeSequence:4:1}"
AdjustMousePos UInput[2] "${escapeSequence:5:1}"
else
UInput[0]=$(printf 'Mouse-\\x%02x %q' "'${escapeSequence:3:1}" "${escapeSequence:4}")
fi
;;
${CSI}[0-9]*[ABCDEFHIOZPQRSz~])
local CSI_Params=( ${escapeSequence//[!0-9]/ } )
local CSI_Func="${escapeSequence:${#escapeSequence}-1}"
case "${CSI_Func}" in
z) # Sun Function Keys
UInput[0]="${SunKeybFntKeys[${CSI_Params[0]}]-}"
if [ -n "${UInput[0]}" ]; then
[ ${#CSI_Params[@]} -le 1 ] || UInput[0]="${KeyModifiers[${CSI_Params[1]}]}-${UInput[0]}"
else
UInput[0]="CSI ${CSI_Params[*]} ${CSI_Func}"
fi
;;
'~') # Function Keys
UInput[0]="${KeybFntKeys[${CSI_Params[0]}]-}"
if [ -n "${UInput[0]}" ]; then
[ ${#CSI_Params[@]} -le 1 ] || UInput[0]="${KeyModifiers[${CSI_Params[1]}]}-${UInput[0]}"
else
UInput[0]="CSI ${CSI_Params[*]} ${CSI_Func}"
fi
;;
A|B|C|D|E|F|H|I|O|Z|P|Q|R|S)
ord_eascii CSI_Func "${CSI_Func}"
UInput[0]="${KeybFntKeysAlt[${CSI_Func}]}"
if [ -n "${UInput[0]}" ]; then
[ ${#CSI_Params[@]} -le 1 ] || UInput[0]="${KeyModifiers[${CSI_Params[1]}]}-${UInput[0]}"
else
UInput[0]="CSI ${CSI_Params[*]} ${CSI_Func}"
fi
;;
*)
UInput[0]="CSI ${CSI_Params[*]} ${CSI_Func}"
;;
esac
;;
${SS3}*[ABCDEFHPQRSIO~])
local SS3_Params=( ${escapeSequence//[!0-9]/ } )
local SS3_Func="${escapeSequence:${#escapeSequence}-1}"
case "${SS3_Func}" in
A|B|C|D|E|F|H|P|Q|R|S|~)
ord_eascii SS3_Func "${SS3_Func}"
UInput[0]="${KeybFntKeysAlt[${SS3_Func}]-}"
if [ -n "${UInput[0]}" ]; then
[ ${#SS3_Params[@]} -lt 1 ] || UInput[0]="${KeyModifiers[${SS3_Params[0]}]}-${UInput[0]}"
else
UInput[0]="SS3 ${SS3_Params[*]-} ${SS3_Func}"
fi
;;
*)
UInput[0]="SS3 ${SS3_Params[*]-} ${SS3_Func}"
;;
esac
;;
$'\e'[[:cntrl:]])
ord_eascii UInput[0] "${escapeSequence:1:1}"
UInput[0]="${C1CtrlCharsAlt[${UInput[0]}]:-}"
[ -n "${UInput[0]:-}" ] || UInput[0]="$(printf "%q" "${escapeSequence}")"
;;
$'\e') UInput[0]="ESC" ;;
*)
UInput[0]="$(printf "%q" "${escapeSequence}")"
;;
esac
;;
*)
ord_eascii UInput[0] "${escapeSequence}"
UInput[0]="${C0CtrlChars[${UInput[0]}]:-}"
[ -n "${UInput[0]:-}" ] || UInput[0]="$(printf '%q' "'${escapeSequence}")"
;;
esac
fi
echo -n "${mouse_off}"
}
The ReadKey function can then be called in this manor.
function HandleKey { local -a UInput while true; do if ReadKey ; then case "${UInput[0]:-}" in CR|NULL|LF|q) echo "\"${UInput[*]-}\"" break ;; *) echo "\"${UInput[*]-}\"" ;; esac fi done } HandleKey