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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE. .\" SUCH DAMAGE.
.\" .\"
.\" @(#)minherit.2 8.1 (Berkeley) 6/9/93 .\" @(#)minherit.2 8.1 (Berkeley) 6/9/93
.\" .\"
.Dd October 30, 2007 .Dd March 15, 2017
.Dt MINHERIT 2 .Dt MINHERIT 2
.Os .Os
.Sh NAME .Sh NAME
.Nm minherit .Nm minherit
.Nd control the inheritance of pages .Nd control the inheritance of pages
.Sh LIBRARY .Sh LIBRARY
.Lb libc .Lb libc
.Sh SYNOPSIS .Sh SYNOPSIS
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This option also has an unfortunate side effect of causing the parent This option also has an unfortunate side effect of causing the parent
address space to become copy-on-write when the parent forks. address space to become copy-on-write when the parent forks.
If the original mapping was If the original mapping was
.Dv MAP_SHARED , .Dv MAP_SHARED ,
it will no longer be shared in the parent it will no longer be shared in the parent
after the parent forks and there is no way to get the previous after the parent forks and there is no way to get the previous
shared-backing-store mapping without unmapping and remapping the address shared-backing-store mapping without unmapping and remapping the address
space in the parent. space in the parent.
.It Dv INHERIT_ZERO
This option causes the address space in question to be mapped as new
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Change from passive to active and edit a bit:

Cause the address space in question to be mapped as new
anonymous pages which are initialized to all zero bytes in the
child process.
wblock: Change from passive to active and edit a bit: ```Cause the address space in question to be…
anonymous pages,
which would be initialized to all zero bytes,
in the child process.
.El .El
.Sh RETURN VALUES .Sh RETURN VALUES
.Rv -std minherit .Rv -std minherit
.Sh ERRORS .Sh ERRORS
The The
.Fn minherit .Fn minherit
system call will fail if: system call will fail if:
.Bl -tag -width Er .Bl -tag -width Er
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.Xr rfork 2 .Xr rfork 2
.Sh HISTORY .Sh HISTORY
The The
.Fn minherit .Fn minherit
system call first appeared in system call first appeared in
.Ox .Ox
and then in and then in
.Fx 2.2 . .Fx 2.2 .
.Pp
The
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This "The" is not necessary.

wblock: This "The" is not necessary.
.Dv INHERIT_ZERO
support first appeared in
.Ox 5.6
and then in
.Fx 12.0 .
.Sh BUGS .Sh BUGS
Once you set inheritance to Once you set inheritance to
.Dv MAP_PRIVATE .Dv MAP_PRIVATE
or or
.Dv MAP_SHARED , .Dv MAP_SHARED ,
there is no way to recover the original copy-on-write semantics there is no way to recover the original copy-on-write semantics
short of unmapping and remapping the area. short of unmapping and remapping the area.