REQUIRED PROGRAMS
n/wireless-tools
n/wpa_supplicant

RECOMMENDED FIRMWARE
n/ipw2100-fw
n/ipw2200-fw
n/zd1211-firmware

OPTIONAL, BUT RECOMMENDED PROGRAM
system/lshw on SBo

FOUND=`/bin/grep "wlan0" /proc/net/dev`
 if  [ -n "$FOUND" ] ; then
  echo WiFi Card Existent
  #unblock radio
  /usr/sbin/rfkill unblock all
  # NetConf
  /usr/bin/killall wpa_supplicant 1> /dev/null 2> /dev/null
  /sbin/ip link set wlan0 down
  /sbin/ip link set wlan0 up
  /sbin/ip address flush dev wlan0
  sleep 1
  /usr/sbin/iw dev wlan0 connect ESSIDNAME
  sleep 1
  /usr/sbin/wpa_supplicant -D nl80211 -i wlan0 -B -c /etc/wpa_supplicant.conf
  /sbin/ip -4 address add 192.168.1.100/24 broadcast 192.168.1.255 dev wlan0
  /sbin/ip route add default via 192.168.1.1
fi

list="a1 b2 c3"
vlist=$(echo $list|sed "s/ /\n/g")
echo please select an item in the list below:
echo "$vlist"
read -p "what is your choice? " choice
if ! echo "$list"|grep -q "$choice"; then
    echo "not in the list"
else
    echo you have selected $choice
fi

$ shellcheck myscript
 
Line 21:
    ((COUNT++))
    ^-- SC2039: In POSIX sh, standalone ((..)) is undefined.
           ^-- SC2039: In POSIX sh, ++ is undefined.
 
Line 24:
  if lshw &> /dev/null; then
          ^-- SC2039: In POSIX sh, &> is undefined.
 
Line 28:
    for ((i=0; i<NUMDEV; i++)); do
    ^-- SC2039: In POSIX sh, arithmetic for loops are undefined.
                          ^-- SC2039: In POSIX sh, ++ is undefined.
 
Line 38:
  LIST=$(for ((i=0; i<NUMDEV; i++)); do eval echo -n \$LINE"$i"%; done)
         ^-- SC2039: In POSIX sh, arithmetic for loops are undefined.
                               ^-- SC2039: In POSIX sh, ++ is undefined.
 
Line 42:
  select WIFIDEV in $LIST; do
  ^-- SC2039: In POSIX sh, select loops are undefined.
 
Line 43:
    [[ -n "$WIFIDEV" ]] || { echo "Invalid choice. Please try again." >&2; continue; }
    ^-- SC2039: In POSIX sh, [[ ]] is undefined.

#!/bin/sh

LIST=$(ifconfig -a | grep flags | cut -d: -f1)

# LIST=$(/sbin/iwconfig 2> /dev/null | /usr/bin/grep ESSID | cut -d' ' -f1)
# Count how many devices were found
NUMDEV=$(echo "$LIST" | wc -l)

# If only one device, set it automatically
if [ "$NUMDEV" -eq 1 ]; then
  WIFIDEV=$LIST
  # If no devices, exit the script
elif [ "$NUMDEV" -eq 0 ]; then
  echo "No wireless devices found. Please check hardware/drivers and try again."
  exit 1
# Otherwise loop through the devices and allow the user to select one
else
  COUNT=0

  # Create a fake array
  for i in $LIST; do
    eval LINE$COUNT="$i"
    COUNT=$((COUNT+1))
  done
  
  # Loop through array
  i=0
  while [ "$i" -lt "$NUMDEV" ]; do
    eval DEVICE="\$LINE$i"
    LSHWINFO=$(lshw -class network | /usr/bin/grep -B 4 "logical name" | /usr/bin/grep -B 4 "$DEVICE" | head -2)
    PRODUCT=$(echo "$LSHWINFO" | head -1 | cut -d: -f2-)
    VENDOR=$(echo "$LSHWINFO" | tail -1 | cut -d: -f2-)
    eval LINE"$i"=\""$DEVICE" -- "$VENDOR" "$PRODUCT"\"
    i=$((i+1))
  done
  
  
  # Recombine the list and use the % symbol as a delimeter
  LIST=$(i=0; while [ "$i" -lt "$NUMDEV" ]; do eval echo -n \$LINE"$i"%; i=$((i+1)); done)
  IFS='%'
  
  # Future menu to allow selection of WIFIDEV

fi
echo "$WIFIDEV"