Output process status command ps meaning behind a plus sign S

Recently discovered a problem, ps command output inside process status is the meaning of S +, and many online article said that indicate process "is located in the daemon group."

       The following example command output ps Description:

    SLEEP D uninterruptible Uninterruptible (usually the IO) 
    R & lt running, or process queue 
    S lies dormant 
    T track stops or 
    Z zombie 
    W into the switching memory (starting from the kernel invalid 2.6) 
    X-die process


     <     higher priority stage 
    N low priority 
    L some pages are locked into memory 
    s comprising subprocess
     +     in the background process group; 
    L multi-threading, thread cloned multi -threaded ( the using CLONE_THREAD, like the NPTL pthreads do )

       But this is not right, followed by a plus sign describes the processes that are "located in the foreground process group." That is the process you can use the keyboard output. Here an experiment to prove this point:

 

       First, a conversation execute a command in a terminal sleep, let it run in the foreground.

       Then, another start a terminal session, start a sleep command running in the background

       Use ps view the process status

       As can be seen in the foreground process state is S +, and sleep state process in the background is S

 

       Search Help ps command, say "is in the foreground process group", can also prove me say this.

 

       Ps command output spread of the Internet is very much the wrong explanation, I write this article, I hope to correct it