storagealert.service

[Unit]
Description=Alerts admin if storage is running low
Wants=storagealert.timer

[Service]
Type=oneshot
ExecStart=/usr/local/sbin/storagealert

[Install]
WantedBy=multi-user.target

storagealert.sh

#!/bin/bash

# Setup:
# 0. Have a mail server set up, or something that provides `sendmail` with proper sender permissions.
# 1. Adjust the $drive, $buckets, $from and $to variables below to suit your needs.
# 2. Create /var/local/storagealert/$drive.txt and write 0 to it.
# If using systemd:
#   3. Put this script at /usr/local/sbin/storagealert with chmod 0755.
#   4. Put the storagealert.service and storagealert.timer files in /etc/systemd/system/.
#   5. Run:
#      systemctl daemon-reload
#      systemctl enable storagealert.timer
#      systemctl start storagealert.timer
# If using cron:
#   3. Put this script at /etc/cron.hourly/storagealert with chmod 0755.

set -e;

drive='PLACEHOLDER';
buckets=('95' '90' '80');
from='[email protected]';
to='[email protected]';

pct="$(df --output=pcent "/dev/$drive" | egrep -v '^Use%$')";
if [ "$(wc -l <<<"$pct")" -ne '1' ]; then
    echo '`df` returned multiple lines of output:' >&2;
    echo "$pct" >&2;
    exit 1;
fi;

if ! grep -Pq '^\s*\d+%$' <<<"$pct"; then
    echo '`df` returned bad percentage:' >&2;
    echo "$pct" >&2;
    exit 1;
fi;

pct="$(sed -E 's#^[[:space:]]*([[:digit:]]+)%$#\1#' <<<"$pct")";
old="$(cat "/var/local/storagealert/$drive.txt")";
echo "$pct" >"/var/local/storagealert/$drive.txt";

do_mail=false;
crossed=0;
for b in "${buckets[@]}"; do
    if [ "$pct" -ge "$b" ] && [ "$old" -lt "$b" ]; then
        do_mail=true;
        crossed="$b";
        break;
    fi;
done;

if "$do_mail"; then
    sendmail -t <<EOF
From: $from
To: $to
Subject: Storage more than $crossed% full
Content-Type: text/plain; charset="US-ASCII"

Drive $drive is $pct% full.

EOF
fi;

storagealert.timer

[Unit]
Description=Run storagealert every hour
Requires=storagealert.service

[Timer]
Unit=storagealert.service
OnCalendar=*-*-* *:00:00

[Install]
WantedBy=timers.target

Just curious I know this is totally unrelated and I didn't know how to communicate to you. Do you know of any way to downgrade the firmware on an Apple Lightning USB Adapter? I'm assuming the answer would be somewhere in com.apple.mobileasset.mobileaccessoryupdate. Thank you.

You could've gotten my email address from so many places...
But no, I don't.