flock search test

.bash

function initializeBuiltins {
        local -
        typeset -a a
        typeset x y z
        set +m

        typeset libdir=${fsRoot%%+(/)}/usr/lib64
        [[ -d ${libdir}/bash ]] || libdir=${rootPath%%+(/)}/lib64
        for x in "${libdir}"/{ctypes.so,bash/!(hello|truefalse|mypid|necho|*.*)}; do
                if [[ $(file -b --mime-type -- "$x") == 'application/x-sharedlib' && !$? -ne 0 ]]; then
                        nm -CDj --without-symbol-versions -- "$x" |
                                while IFS= read -r y; do
                                        [[ $y =~ ^(.+)_struct$ ]] || continue
                                        a+=("${BASH_REMATCH[1]}")
                                done

                        (( PIPESTATUS[0] )) || enable -f "$x" -- "${a[@]}" 2>&3
                        unset -v 'a[@]'
                fi
        done 3>/dev/null

        for x in ln head rm stat; do
                printf -v y '%q%.s' "$(type -P "$x")" "$((z=$?))"
                let z && continue
                eval -- \
                        function "${x}"  { command -- "$y" \"\$@\" \; } \; \
                        function "${x}2" { builtin -- "$x" \"\$@\" \; }
        done
        return 0
}

function f {
        local -
        set +m
        typeset lock x= pid=$BASHPID
        typeset -a output
        typeset -g lockfile
        # trap '${lockfile:+\:} exit; rm -f -- "$lockfile"' EXIT
        mktemp -v lockfile >/dev/null || return
        {
                unlink "$lockfile"
                for lock in '' x s; do
                        lslocks -p "$pid"
                        x= ${x+\:}
                        ${x:+\:} flock -u 3
                        ${x:+\:} flock "-${lock}" 3
                        lsof -ap "$pid" -d 3 -F lfG0 +f g | mapfile -td '' output
                        printf '%s ' "${output[@]}"; echo
                        ${lock:+\:} unset -v x
                done
        } 3<"$lockfile"
}
initializeBuiltins
echo; f; echo