How to Hide PID and Exit Status When Running a Background Command in Terminal

Question

I have a text file that has over a hundred lines, each of which is an sh command:

echo foo
...
echo bar

I'm looking for an sh command that I can invoke from a terminal which will run the command from said file associated with a specified line number. I do not want the terminal to show the usual system-related content that is normally associated with commands run in a terminal.

For example, if I use something like xdotool type "$(sed -n 1p file)" & (note that I'm open to a more elegant command),

I get the following terminal output:

[1] 9531
user@host:~$ echo foo

I wish to suppress the [1] 9531 line. Please keep in mind, however, that I do not wish to suppress the echo bar line, as that is where I have a chance to verify that I'm about to execute the desired command and not something else. Nor do I wish for any text to be displayed to the left of the command prompt.

I then hit the <Enter> key of my keyboard and get:

foo
[1]+  Done                    xdotool type "$(sed -n 1p file)" &
user@host:~$

I wish to suppress the [1]+ Done... line.

How can I suppress the terminal output of said two lines? I've tried every redirect scheme I can find, with no joy.

Answer 1

Just to simplify, what you are seeing is the normal output when you run a command in the background (& symbol). One can see the same if one runs this simplified version:

ls &

To avoid seeing that output, you can sorround your command with parenthesis:

(ls &)

Or, in your case

(xdotool type "$(sed -n 1p file)" &)

In your particular case, it doesn't seem you really need the &, so it may be easier to remove it from your command:

xdotool type "$(sed -n 1p file)"

PS

If you want to run all the file sequentially from beginning to end, you might prefer doing something like

x=0

and then, for each line, run

x=$((x+1)); (xdotool type "$(sed -n "${x}p" file)" &)

This way you don't need to modify the number each time.

Also have a look at this: How to interactively run all commands in a file