util-linux/bash-completion/lsblk

_lsblk_module()
{
	local cur prev OPTS
	COMPREPLY=()
	cur="${COMP_WORDS[COMP_CWORD]}"
	prev="${COMP_WORDS[COMP_CWORD-1]}"
	case $prev in
		'-e'|'--exclude'|'-I'|'--include')
			local MAJOR I J
			MAJOR=''
			for I in /sys/dev/block/*; do
				J=${I##*/}
				MAJOR="$MAJOR ${J%%:*}"
			done
			# FIXME: how to append to a string with compgen?
			compopt -o nospace
			COMPREPLY=( $(compgen -W "$MAJOR" -S ',' -- $cur) )
			return 0
			;;
		'-o'|'--output')
			# FIXME: how to append to a string with compgen?
			OUTPUT="NAME KNAME MAJ:MIN FSTYPE MOUNTPOINT
				LABEL UUID PARTLABEL PARTUUID RA RO RM
				MODEL SIZE STATE OWNER GROUP MODE
				ALIGNMENT MIN-IO OPT-IO PHY-SEC LOG-SEC
				ROTA SCHED RQ-SIZE TYPE DISC-ALN
				DISC-GRAN DISC-MAX DISC-ZERO WSAME WWN
				RAND PKNAME HCTL TRAN REV VENDOR"
			compopt -o nospace
			COMPREPLY=( $(compgen -W "$OUTPUT" -S ',' -- $cur) )
			return 0
			;;
		'-h'|'--help'|'-V'|'--version')
			return 0
			;;
	esac
	case $cur in
		-*)
			OPTS="--all
				--bytes
				--nodeps
				--discard
				--exclude
				--fs
				--help
				--include
				--ascii
				--list
				--perms
				--noheadings
				--output
				--pairs
				--raw
				--inverse
				--topology
				--scsi
				--help
				--version"
			COMPREPLY=( $(compgen -W "${OPTS[*]}" -- $cur) )
			return 0
			;;
	esac
	local DEVS
	DEVS=''; while read dev; do DEVS+="$dev " ; done < <(lsblk -pnro name)
	COMPREPLY=( $(compgen -W "$DEVS" -- $cur) )
	return 0
}
complete -F _lsblk_module lsblk