Background FTP session, with processable output

ftp.sh

#!/bin/bash

# Make the fifos
mgmtFifo="/tmp/.ftp.mgmt.fifo"
cmdFifo="/tmp/.ftp.cmd.fifo"
outFifo="/tmp/.ftp.out.fifo"
mkfifo "$mgmtFifo"
mkfifo "$cmdFifo"
mkfifo "$outFifo"

# We may want a way to echo back for the sub-shell
exec 4>&1
# Open fifos with r/w
exec 5<>"$mgmtFifo"
exec 6<>"$cmdFifo"
exec 7<>"$outFifo"

# No more stdin (&0)
exec 0>&-

{
	ftp -v example.com <&6 >&7 &
	while true; do
		read -u5 mgmtString
		[[ "$mgmtString" == "exit-subshell" ]] && exit 0
		sleep 1
	done
} &

echo "prompt" >&6
echo "ls" >&6

# Process ftp output until we say so
startSeen=0
finishedProcessing=0
while [[ "$finishedProcessing" -eq 0 ]]; do
	read -u7 ftpOutput
	[[ "$ftpOutput" == "Interactive mode off." ]] && startSeen=1
	if [[ "$startSeen" -eq 1 ]]; then
		if [[ "$ftpOutput" != "226 Directory send OK." ]]; then
			if [[ ! "$ftpOutput" =~ ^[1-6][0-5][0-9]\  ]]; then
				filename="$(echo $ftpOutput | cut -d' ' -f9)"
				echo "$filename"
			fi
		else
			finishedProcessing=1
		fi
	fi
done
echo "quit" >&6
sleep 1
echo "exit-subshell" >&5