How to sleep for 1 second between each xargs command?

问题

For example, if I execute

ps aux | awk '{print $1}' | xargs -I {} echo {}

I want to let the shell sleep for 1 second between each echo.

How can I change my shell command?

回答1:

You can use following syntax:

ps aux | awk '{print $1}' | xargs -I % sh -c '{ echo %; sleep 1; }'

Be careful with spaces and semicolons though. After every command between brackets, semicolon is required (even after last one).

回答2:

Replace echo by some shell script named sleepecho containing

 #!/bin/sh
 sleep 1
 echo $*

回答3:

If your awk supports it:

ps aux | awk '{ system("sleep 1"); print $1 }' | xargs -I {} echo {}q

or skip awk and xargs altogether

ps aux | while read -r user rest;
    echo $user
    sleep 1;
done

来源：https://stackoverflow.com/questions/15153240/how-to-sleep-for-1-second-between-each-xargs-command