centos man page for wait_task_stopped

WAIT_TASK_STOPPED(9)						   Driver Basics					      WAIT_TASK_STOPPED(9)

NAME
       wait_task_stopped - Wait for TASK_STOPPED or TASK_TRACED

SYNOPSIS
       int wait_task_stopped(struct wait_opts * wo, int ptrace, struct task_struct * p);

ARGUMENTS
       wo
	   wait options

       ptrace
	   is the wait for ptrace

       p
	   task to wait for

DESCRIPTION
       Handle sys_wait4 work for p in state TASK_STOPPED or TASK_TRACED.

CONTEXT
       read_lock(tasklist_lock), which is released if return value is non-zero. Also, grabs and releases p->sighand->siglock.

RETURNS
       0 if wait condition didn't exist and search for other wait conditions should continue. Non-zero return, -errno on failure and p's pid on
       success, implies that tasklist_lock is released and wait condition search should terminate.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014						      WAIT_TASK_STOPPED(9)