.TH pollhead "" "" "STREAMS Data Structure"
.PC "Structure for a STREAMS poll head"
.B "#include <sys/poll.h>"
.PP
The structure
.B pollhead
is used in System V polling.
This structure is meant to be totally opaque; no access to its internal
structure is permitted.
.PP
A driver must provide one
.B pollhead
structure for each minor device that it supports.
It must call
.B phalloc()
to allocate the
structure; it must call
.B phfree()
to free the structure once it is no longer needed.
A DDI/DKI driver can use a
.B pollhead
structure only if
.B phalloc()
has allocated and initialized it.
.PP
The driver entry point
.B chpoll
gives access to the driver's polling routine.
.SH "See Also"
.B
chpoll,
DDI/DKI data structures,
phalloc(),
phfree()
.R
