Piping echo into sendmail in rc.local fails

Question

I'm trying to get my system to send me an email when the system boots. Using the following command works as intended:

echo -e "TO:[email protected] \nSUBJECT:System Booted \n\nBeware I live! \n"$1 | sendmail -t -vs

But if I add it to rc.local like so:

#!/bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.

#----- Print the IP address
#_IP=$(hostname -I) || true
#if [ "$_IP" ]; then
#  printf "My IP address is %s\n" "$_IP"
#fi

#----- Notify on boot
/home/alex/notify/boot.sh "`date`"

exit 0

I get:

sendmail: No recipients specified although -t option used

Why is this failing?

Answer 1

Problem in using bash/zsh vs /bin/sh

Bash and Zsh have builtin echo with option -e, but a system /bin/echo - not. Compare:

• /bin/echo -e "TO:[email protected] \nSUBJECT:System Booted \n\nBeware I live! \n"
• echo -e "TO:[email protected] \nSUBJECT:System Booted \n\nBeware I live! \n"

You may use script like this:

#!/bin/sh
sendmail -t -vs <<EOF
TO:[email protected]
SUBJECT:System Booted

Beware I live!
$1
EOF