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* Add .Vt in the right places, transform some .Fa to .Vt, depending
    on discussion context.

  * When refering to the function malloc(), use .Fn, and not .Xr.

  * Add `The' to prefix a sentence when describing a function, so
    it results in ``The xxx() function..."

  * Use `system call' instead of `syscall'.

  * Improve the sentence which discusses accept_filt_generic_mod_event();
    Talk about moduledata_t, and refer to the DECLARE_MODULE(9) manual
    page.

  * Properly markup .An (Author Name) throughout the AUTHORS section.
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hmp 2003-10-23 05:01:30 +00:00
parent ff12dfc2e8
commit d5bc42e59f
1 changed files with 38 additions and 22 deletions
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60
share/man/man9/accept_filter.9
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@ -60,7 +60,9 @@ of
.Dv SO_ACCEPTFILTER .
.Sh IMPLEMENTATION NOTES
A module that wants to be an accept filter
must provide a struct accept_filter to the system:
must provide a
.Vt struct accept_filter
to the system:
.Bd -literal
struct accept_filter {
char accf_name[16];
@ -73,51 +75,58 @@ struct accept_filter {
.Pp
The module should register it with the function
.Fn accept_filt_add ,
passing a pointer to a struct accept_filter, allocated with
.Xr MALLOC 9
passing a pointer to a
.Fa struct accept_filter ,
allocated with
.Fn malloc .
.Pp
The fields of
.Fa struct accept_filter
.Vt struct accept_filter
are as follows:
.Bl -tag -width accf_callbackXXX
.It accf_name
.It Vt accf_name
Name of the filter;
this is how it will be accessed from userland.
.It accf_callback
.It Fn accf_callback
The callback that the kernel will do
once the connection is established.
It is the same as a socket upcall
and will be called when the connection is established
and whenever new data arrives on the socket,
unless the callback modifies the socket's flags.
.It accf_create
.It Fn accf_create
Called whenever a
.Xr setsockopt 2
installs the filter onto
a listening socket.
.It accf_destroy
.It Fn accf_destroy
Called whenever the user removes the accept filter on the socket.
.El
.Pp
The
.Fn accept_filt_del
passed the same string used in accept_filter.accf_name during registration
with
function
passed the same string used in
.Va accept_filter.accf_name
during registration with
.Fn accept_filt_add ,
the kernel will then disallow and further userland use of the filter.
.Pp
The
.Fn accept_filt_get
is used internally to locate which accept filter to use via the
function is used internally to locate which accept filter to use via the
.Fn setsockopt
syscall.
system call.
.Pp
The
.Fn accept_filt_generic_mod_event
provides a simple way to avoid duplicate
code for accept filters which don't use
argument field to load and unload
themselves. It is a function that can be
put in the load/unload struct
for the
.Fn DECLARE_MODULE
function provides a simple way to avoid duplication of code
for accept filters which don't use the argument field to load
and unload themselves.
This function can be used in the
.Vt moduledata_t
struct for the
.Xr DECLARE_MODULE 9
macro.
.Sh SEE ALSO
.Xr setsockopt 2 ,
@ -129,7 +138,14 @@ The accept filter mechanism was introduced in
.Fx 4.0 .
.Sh AUTHORS
This manual page was written by
.An -nosplit
.An Alfred Perlstein ,
Sheldon Hearn and Jeroen Ruigrok van der Werven.
The accept filter concept was pioneered by David Filo at Yahoo!
and refined to be a loadable module system by Alfred Perlstein.
.An Sheldon Hearn
and
Jeroen Ruigrok van der Werven.
.Pp
The accept filter concept was pioneered by
.An David Filo
at Yahoo!
and refined to be a loadable module system by
.An Alfred Perlstein.