Bash unexpected redirect.

NetEng1 · 11-10-2015, 07:37 AM

I am attempting to write a bash script that backs up a mysql database and sends an e-mail stating whether if failed or was successful. I am using the following:

Code:

if [ $check != 0 ]; then
       mail -s "Mysql Backup Successful" User1@domain.com <<< " I do not believe it, Please verify."

else

       mail -s "Mysql Backup FAILED" User1@domain.com <<< " The blasted thing FAILED, Check your stuff."
fi

When I run it, I get "unexpected redirect" error.

I created separate scripts for each case and just copied and pasted the "mail -s ...." lines into them respectively. Then I called the newly create scripts as follows:

Code:

if [ $check != 0 ]; then

        /home/fmadmin/mail_success.sh
else

        /home/fmadmin/mail_fail.sh
fi

Now it works fine. Can someone advise me what is wrong with the first approach?

Thanks,
Keith

rtmistler · 11-10-2015, 08:04 AM

Wondering myself, because a modified form of your first rendition does work for me, providing I put in a relevant email address for my machine. The only other difference is that my if test is:

Code:

if [ 1 == 1]; then

merely because I didn't take the time to have a $check variable in my script.

Note that when you type "<<<" it can cause behavior like this, which auto-appears in my editor:

Code:

<<EOF
<
EOF

But if I were to inadvertently not erase the EOF at the bottom it would just tell me that it is an invalid command.

grail · 11-10-2015, 09:58 AM

So to confirm, you have a script with ONLY those 5 lines and you get the error?

Also, have you tried using set -xv in your script to see what is happening?

berndbausch · 11-10-2015, 11:38 AM

I wonder if your interactive shell is a different shell than the one that executes your scripts. The <<< construct is only supported by bash, I believe.

berndbausch · 11-10-2015, 11:47 AM

Code:

bash $ wc <<< "howsit goin?"
 1  2 13
bash $ dash
dash $ wc <<< "howsit goin?"
dash: Syntax error: redirection unexpected
dash $

chrism01 · 11-10-2015, 04:18 PM

I'd also add a couple of syntax points.

1. use [[ ]] rather than [ ] http://tldp.org/LDP/abs/html/testcon...ml#DBLBRACKETS
2. use the correct comparison op ( -ne rather than != ) http://tldp.org/LDP/abs/html/comparison-ops.html