How to execute a command repeatedly with different arguments?

Question

I'm on Ubuntu. I copied some arguments (separated by newline) and I can use xsel to print them out like this

$ xsel
arg1
arg2
arg3
arg4
...

Now, I want to use each of these arguments for another command and execute that command as many times as there are arguments.

So I tried

$ xsel | mycommand "constantArgument" $1

However, this executed mycommand only for the first argument. How can I execute it for every argument?

Edited the question to reflect the fact that there is more than one argument to mycommand. — Wes, yesterday

Rahul Patil · Accepted Answer · 2014-03-19 20:06:07Z

up vote 11 down vote accepted

You can simply use xargs

xsel | xargs -n1 echo mycommand

-n1 means one arg for mycommand, but it's just dry run, it will show what going to be run, to run it remove echo

For constant Argument

xsel | xargs -I {} -n1 echo mycommand "constantArgument" {}

answered yesterday

Rahul Patil
5,80031231

What if "mycommand" expects more than one argument out of which the xsel contains just one argument? – Wes yesterday

xsel | xargs -n1 echo mycommand -more-arg – Rahul Patil yesterday

xsel | xargs -n2 echo mycommand two arg per command – Rahul Patil yesterday

Thanks. This is useful. – Wes yesterday

You are most welcome, don't forgot to accept answer if you find it useful. – Rahul Patil yesterday

orion · Answer 2 · 2014-03-19 20:02:32Z

xsel | while read line; do mycommand "$line"; done

Or something similar. You can also use xargs, which is a very powerful command for manipulation of command line arguments.

mikeserv · Answer 3 · 2014-03-20 12:04:09Z

For a little customizability:

printf "${CMD} %s ${ARG2}\n" `xsel` | sh -n

You can remove the -noexecute flag after you've seen how it works.

If it works for you, you can drop sh entirely and do this instead:

. <<HERE /dev/stdin
    $(printf "${CMD} %s ${ARG2}\n" `xsel`)
HERE

Or faster:

printf "${CMD} %s ${ARG2}\n" `xsel` | . /dev/stdin

Either way is easy and will do it.

3 Answers