Bashscripts.org

I have a simple script for ssh-ing messages to my wife through the Ubuntu notification system (notify-osd):


Now, the $1 is the problem I'm having, and I'll get to that in a second.

I should say first that this command works as an alias in the remote-host, but with the ssh part stripped off, such that: After SSH-ing to the remote machine, type 'chat' at a prompt, and enter your message "surrounded by double quotes" to have it appear as a notification bubble on the remote screen.

In script form, without the $1 variable there, I get an error, "No summary specified." With the $1 variable, if I type more than one word separated with a space, I get the error "Invalid number of options." A little research led me to believe that if I substituted in $@ instead of $1, it might work better, but it doesn't.

Seems to me that there has to be a variable there - what should I use?

An update of sorts:From my terminal (not the script) it will work like this


I don't even know how to ask any more. Wrapping the DISPLAY & notify-send commands in single quotes makes it functional. How can I make the double-quoted text a variable that I can use in a command prompt; e.g., chat "This isn't just a test any more." and have it pass through to notify-send on the remote host?

What happens when you run that in the script?

Would it work if you have some thing like this?

The message needs to be enclosed in quotes (either single or double, I think) for notify-send. But, you need to escape them in the script.

I get the same errors if I try to make the msg='$1' or msg='$@' variables. Again, with $1, I can send single-word messages, or whole lines of text as long as I don't use any spaces.

I see what you're saying, though. But having the message included in the script itself and having to open, edit, save, then execute it every time I use it is actually a little worse than having to ssh to the other computer and the execute the command locally.

I'll see what I can come up with along these lines.

The final, working copy, as such

Which is more or less how you showed me above. I guess I was just cross-eyed after staring at it and googling for so long.

Thanks for the help!

I'm glad it's working for you.

The important lesson to take home here is the difference between using double quotes, single quotes, or no quotes.

As a general rule, double quotes allow for interpolating, which is the expansion of variables, among other things. That's why message="$@" works for you, but message='$@' would not.

Single quotes do not allow for interpolation. Since I didn't have a variable in my string, I just used single quotes.

The man page for notify-send is nearly useless, but I assumed that it takes a string as an argument (one argument). If the string is not enclosed in quotes, then words separated by spaces will look like multiple arguments; we enclose them in quotes (single or double) to make it a single string. A more subtle note is that we escape the quotes so that bash doesn't interpret them in the script, and just passes normal quotes to notify-send.

It's all a little tricky, but hopefully this cleared up some issues for you.