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If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner] .TH DOOR_SERVER_CREATE 3C "May 12, 2017" .SH NAME door_server_create \- specify an alternative door server thread creation function .SH SYNOPSIS .LP .nf \fBcc\fR \fB-mt\fR [ \fIflag\fR... ] \fIfile\fR... [ \fIlibrary\fR... ] #include <door.h> \fBvoid (*)(door_info_t *)\fR \fBdoor_server_create\fR(\fBvoid (*\fR\fIcreate_proc\fR)(door_info_t *)); .fi .SH DESCRIPTION .LP Normally, the doors library creates new door server threads in response to incoming concurrent door invocations automatically. There is no pre-defined upper limit on the number of server threads that the system creates in response to incoming invocations (1 server thread for each active door invocation). These threads are created with the default thread stack size and POSIX (see \fBstandards\fR(5)) threads cancellation disabled. The created threads also have the \fBTHR_BOUND\fR | \fBTHR_DETACHED\fR attributes for Solaris threads and the \fBPTHREAD_SCOPE_SYSTEM\fR | \fBPTHREAD_CREATE_DETACHED\fR attributes for POSIX threads. The signal disposition, and scheduling class of the newly created thread are inherited from the calling thread (initially from the thread calling \fBdoor_create()\fR, and subsequently from the current active door server thread). .sp .LP The \fBdoor_server_create()\fR function allows control over the creation of server threads needed for door invocations. The procedure \fIcreate_proc\fR is called every time the available server thread pool is depleted. In the case of private server pools associated with a door (see the \fBDOOR_PRIVATE\fR attribute in \fBdoor_create()\fR), information on which pool is depleted is passed to the create function in the form of a \fBdoor_info_t\fR structure. The \fBdi_proc\fR and \fBdi_data\fR members of the \fBdoor_info_t\fR structure can be used as a door identifier associated with the depleted pool. The \fIcreate_proc\fR procedure may limit the number of server threads created and may also create server threads with appropriate attributes (stack size, thread-specific data, POSIX thread cancellation, signal mask, scheduling attributes, and so forth) for use with door invocations. .sp .LP The overall amount of data and argument descriptors that can be sent through a door is limited by both the server thread's stack size and by the parameters of the door itself. See \fBdoor_setparam\fR(3C). .sp .LP The specified server creation function should create user level threads using \fBthr_create()\fR with the \fBTHR_BOUND\fR flag, or in the case of POSIX threads, \fBpthread_create()\fR with the \fBPTHREAD_SCOPE_SYSTEM\fR attribute. The server threads make themselves available for incoming door invocations on this process by issuing a \fBdoor_return\fR(\fBNULL, 0, NULL, 0\fR). In this case, the \fBdoor_return()\fR arguments are ignored. See \fBdoor_return\fR(3C) and \fBthr_create\fR(3C). .sp .LP The server threads created by default are enabled for POSIX thread cancellations which may lead to unexpected thread terminations while holding resources (such as locks) if the client aborts the associated \fBdoor_call()\fR. See \fBdoor_call\fR(3C). Unless the server code is truly interested in notifications of client aborts during a door invocation and is prepared to handle such notifications using cancellation handlers, POSIX thread cancellation should be disabled for server threads using \fBpthread_setcancelstate\fR (\fBPTHREAD_CANCEL_DISABLE\fR, \fINULL\fR). If all doors are created with the \fBDOOR_NO_CANCEL\fR flag (see \fBdoor_create\fR(3C)), the threads will never be cancelled by an aborted \fBdoor_call()\fR call .sp .LP The \fIcreate_proc\fR procedure need not create any additional server threads if there is at least one server thread currently active in the process (perhaps handling another door invocation) or it may create as many as seen fit each time it is called. If there are no available server threads during an incoming door invocation, the associated \fBdoor_call()\fR blocks until a server thread becomes available. The \fIcreate_proc\fR procedure must be MT-Safe. .SH RETURN VALUES .LP Upon successful completion, \fBdoor_server_create()\fR returns a pointer to the previous server creation function. This function has no failure mode (it cannot fail). .SH EXAMPLES .LP \fBExample 1 \fRCreating door server threads. .sp .LP The following example creates door server threads with cancellation disabled and an 8k stack instead of the default stack size: .sp .in +2 .nf #include <door.h> #include <pthread.h> #include <thread.h> void * my_thread(void *arg) { pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL); door_return(NULL, 0, NULL, 0); } void my_create(door_info_t *dip) { thr_create(NULL, 8192, my_thread, NULL, THR_BOUND | THR_DETACHED, NULL); } main(\|) { (void)door_server_create(my_create); \|.\|.\|. } .fi .in -2 .SH ATTRIBUTES .LP See \fBattributes\fR(5) for descriptions of the following attributes: .sp .sp .TS box; c | c l | l . ATTRIBUTE TYPE ATTRIBUTE VALUE _ Architecture all _ Interface Stability Stable _ MT-Level Safe .TE .SH SEE ALSO .LP \fBdoor_bind\fR(3C), \fBdoor_call\fR(3C), \fBdoor_create\fR(3C), \fBdoor_return\fR(3C), \fBpthread_create\fR(3C), \fBpthread_setcancelstate\fR(3C), \fBthr_create\fR(3C), \fBattributes\fR(5), \fBcancellation\fR(5), \fBstandards\fR(5)