proc_ref(D3DK) —

NAME

proc_ref − obtain a reference to a process for signaling .IX \f4proc_ref\fP(D3DK)

SYNOPSIS

void ∗proc_ref();

DESCRIPTION

A non-STREAMS character driver can call proc_ref to obtain a reference to the process in whose context it is running. The value returned can be used in subsequent calls to proc_signal(D3DK) to post a signal to the process. The return value should not be used in any other way (i.e. the driver should not attempt to interpret its meaning.)

RETURN VALUE

An identifier that can be used in calls to proc_signal and proc_unref(D3DK).

LEVEL

Base only.

NOTES

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(D2DK) processing. Requires user context. Does not sleep. Driver defined basic locks, read/write locks, and sleep locks may be held across calls to this function.

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