proc_ref(D3)

NAME
     proc_ref - obtain a reference to a process for signaling

SYNOPSIS
     #include <sys/stream.h>
     #include <sys/ddi.h>
     void *proc_ref(void);

DESCRIPTION
     A non-STREAMS character driver can call proc_ref to obtain a reference to
     the process in whose context it is running.

   Return Values
     proc_ref returns an identifier that can be used in calls to proc_signal
     and proc_unref(D3).

USAGE
     The value returned can be used in subsequent calls to proc_signal(D3) to
     post a signal to the process.  The return value should not be used in any
     other way (that is, the driver should not attempt to interpret its
     meaning).

     Processes can exit even though they are referenced by drivers.  In this
     event, reuse of the identifier will be deferred until all driver
     references are given up.

     There must be a matching call to proc_unref for every call to proc_ref,
     when the driver no longer needs to reference the process.  This is
     typically done as part of close(D2) processing.

     This function requires user context.

   Level
     Base only.

   Synchronization Constraints
     Does not sleep.

     Driver-defined basic locks, read/write locks, and sleep locks may be held
     across calls to this function.

REFERENCES
     proc_signal(D3), proc_unref(D3)