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diff --git a/lib/libc/sys/kqueue.2 b/lib/libc/sys/kqueue.2 deleted file mode 100644 index 066ad717111a..000000000000 --- a/lib/libc/sys/kqueue.2 +++ /dev/null @@ -1,887 +0,0 @@ -.\" Copyright (c) 2000 Jonathan Lemon -.\" All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" -.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND -.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE -.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE -.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE -.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL -.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS -.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) -.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT -.\" 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 -.\" SUCH DAMAGE. -.\" -.Dd March 26, 2023 -.Dt KQUEUE 2 -.Os -.Sh NAME -.Nm kqueue , -.Nm kevent -.Nd kernel event notification mechanism -.Sh LIBRARY -.Lb libc -.Sh SYNOPSIS -.In sys/event.h -.Ft int -.Fn kqueue "void" -.Ft int -.Fn kqueuex "u_int flags" -.Ft int -.Fo kevent -.Fa "int kq" -.Fa "const struct kevent *changelist" -.Fa "int nchanges" -.Fa "struct kevent *eventlist" -.Fa "int nevents" -.Fa "const struct timespec *timeout" -.Fc -.Fn EV_SET "kev" ident filter flags fflags data udata -.Sh DESCRIPTION -The -.Fn kqueue -system call -provides a generic method of notifying the user when an event -happens or a condition holds, based on the results of small -pieces of kernel code termed filters. -A kevent is identified by the (ident, filter) pair; there may only -be one unique kevent per kqueue. -.Pp -The filter is executed upon the initial registration of a kevent -in order to detect whether a preexisting condition is present, and is also -executed whenever an event is passed to the filter for evaluation. -If the filter determines that the condition should be reported, -then the kevent is placed on the kqueue for the user to retrieve. -.Pp -The filter is also run when the user attempts to retrieve the kevent -from the kqueue. -If the filter indicates that the condition that triggered -the event no longer holds, the kevent is removed from the kqueue and -is not returned. -.Pp -Multiple events which trigger the filter do not result in multiple -kevents being placed on the kqueue; instead, the filter will aggregate -the events into a single struct kevent. -Calling -.Fn close -on a file descriptor will remove any kevents that reference the descriptor. -.Pp -The -.Fn kqueue -system call -creates a new kernel event queue and returns a descriptor. -The queue is not inherited by a child created with -.Xr fork 2 . -However, if -.Xr rfork 2 -is called without the -.Dv RFFDG -flag, then the descriptor table is shared, -which will allow sharing of the kqueue between two processes. -.Pp -The -.Fn kqueuex -system call also creates a new kernel event queue, and additionally takes -the -.Fa flags -argument, which is a bitwise-inclusive OR of the following flags: -.Bl -tag -width "KQUEUE_CLOEXEC" -.It Fa KQUEUE_CLOEXEC -The returned file descriptor is automatically closed on -.Xr execve 2 -.El -The -.Ql fd = kqueue() -call is equivalent to -.Ql fd = kqueuex(0) . -.Pp -For compatibility with -.Nx , -the -.Fn kqueue1 -function is provided, which accepts the -.Dv O_CLOEXEC -flag with the expected semantic. -.Pp -The -.Fn kevent -system call -is used to register events with the queue, and return any pending -events to the user. -The -.Fa changelist -argument -is a pointer to an array of -.Va kevent -structures, as defined in -.In sys/event.h . -All changes contained in the -.Fa changelist -are applied before any pending events are read from the queue. -The -.Fa nchanges -argument -gives the size of -.Fa changelist . -The -.Fa eventlist -argument -is a pointer to an array of kevent structures. -The -.Fa nevents -argument -determines the size of -.Fa eventlist . -When -.Fa nevents -is zero, -.Fn kevent -will return immediately even if there is a -.Fa timeout -specified unlike -.Xr select 2 . -If -.Fa timeout -is a non-NULL pointer, it specifies a maximum interval to wait -for an event, which will be interpreted as a struct timespec. -If -.Fa timeout -is a NULL pointer, -.Fn kevent -waits indefinitely. -To effect a poll, the -.Fa timeout -argument should be non-NULL, pointing to a zero-valued -.Va timespec -structure. -The same array may be used for the -.Fa changelist -and -.Fa eventlist . -.Pp -The -.Fn EV_SET -macro is provided for ease of initializing a -kevent structure. -.Pp -The -.Va kevent -structure is defined as: -.Bd -literal -struct kevent { - uintptr_t ident; /* identifier for this event */ - short filter; /* filter for event */ - u_short flags; /* action flags for kqueue */ - u_int fflags; /* filter flag value */ - int64_t data; /* filter data value */ - void *udata; /* opaque user data identifier */ - uint64_t ext[4]; /* extensions */ -}; -.Ed -.Pp -The fields of -.Fa struct kevent -are: -.Bl -tag -width "Fa filter" -.It Fa ident -Value used to identify this event. -The exact interpretation is determined by the attached filter, -but often is a file descriptor. -.It Fa filter -Identifies the kernel filter used to process this event. -The pre-defined -system filters are described below. -.It Fa flags -Actions to perform on the event. -.It Fa fflags -Filter-specific flags. -.It Fa data -Filter-specific data value. -.It Fa udata -Opaque user-defined value passed through the kernel unchanged. -.It Fa ext -Extended data passed to and from kernel. -The -.Fa ext[0] -and -.Fa ext[1] -members use is defined by the filter. -If the filter does not use them, the members are copied unchanged. -The -.Fa ext[2] -and -.Fa ext[3] -members are always passed through the kernel as-is, -making additional context available to application. -.El -.Pp -The -.Va flags -field can contain the following values: -.Bl -tag -width EV_DISPATCH -.It Dv EV_ADD -Adds the event to the kqueue. -Re-adding an existing event -will modify the parameters of the original event, and not result -in a duplicate entry. -Adding an event automatically enables it, -unless overridden by the EV_DISABLE flag. -.It Dv EV_ENABLE -Permit -.Fn kevent -to return the event if it is triggered. -.It Dv EV_DISABLE -Disable the event so -.Fn kevent -will not return it. -The filter itself is not disabled. -.It Dv EV_DISPATCH -Disable the event source immediately after delivery of an event. -See -.Dv EV_DISABLE -above. -.It Dv EV_DELETE -Removes the event from the kqueue. -Events which are attached to -file descriptors are automatically deleted on the last close of -the descriptor. -.It Dv EV_RECEIPT -This flag is useful for making bulk changes to a kqueue without draining -any pending events. -When passed as input, it forces -.Dv EV_ERROR -to always be returned. -When a filter is successfully added the -.Va data -field will be zero. -Note that if this flag is encountered and there is no remaining space in -.Fa eventlist -to hold the -.Dv EV_ERROR -event, then subsequent changes will not get processed. -.It Dv EV_ONESHOT -Causes the event to return only the first occurrence of the filter -being triggered. -After the user retrieves the event from the kqueue, -it is deleted. -.It Dv EV_CLEAR -After the event is retrieved by the user, its state is reset. -This is useful for filters which report state transitions -instead of the current state. -Note that some filters may automatically -set this flag internally. -.It Dv EV_EOF -Filters may set this flag to indicate filter-specific EOF condition. -.It Dv EV_ERROR -See -.Sx RETURN VALUES -below. -.It Dv EV_KEEPUDATA -Causes -.Fn kevent -to leave unchanged any -.Fa udata -associated with an existing event. -This allows other aspects of the event to be modified without requiring the -caller to know the -.Fa udata -value presently associated. -This is especially useful with -.Dv NOTE_TRIGGER -or flags like -.Dv EV_ENABLE . -This flag may not be used with -.Dv EV_ADD . -.El -.Pp -The predefined system filters are listed below. -Arguments may be passed to and from the filter via the -.Va fflags -and -.Va data -fields in the kevent structure. -.Bl -tag -width "Dv EVFILT_PROCDESC" -.It Dv EVFILT_READ -Takes a descriptor as the identifier, and returns whenever -there is data available to read. -The behavior of the filter is slightly different depending -on the descriptor type. -.Bl -tag -width 2n -.It Sockets -Sockets which have previously been passed to -.Xr listen 2 -return when there is an incoming connection pending. -.Va data -contains the size of the listen backlog. -.Pp -Other socket descriptors return when there is data to be read, -subject to the -.Dv SO_RCVLOWAT -value of the socket buffer. -This may be overridden with a per-filter low water mark at the -time the filter is added by setting the -.Dv NOTE_LOWAT -flag in -.Va fflags , -and specifying the new low water mark in -.Va data . -On return, -.Va data -contains the number of bytes of protocol data available to read. -.Pp -If the read direction of the socket has shutdown, then the filter -also sets -.Dv EV_EOF -in -.Va flags , -and returns the socket error (if any) in -.Va fflags . -It is possible for EOF to be returned (indicating the connection is gone) -while there is still data pending in the socket buffer. -.It Vnodes -Returns when the file pointer is not at the end of file. -.Va data -contains the offset from current position to end of file, -and may be negative. -.Pp -This behavior is different from -.Xr poll 2 , -where read events are triggered for regular files unconditionally. -This event can be triggered unconditionally by setting the -.Dv NOTE_FILE_POLL -flag in -.Va fflags . -.It "Fifos, Pipes" -Returns when the there is data to read; -.Va data -contains the number of bytes available. -.Pp -When the last writer disconnects, the filter will set -.Dv EV_EOF -in -.Va flags . -This will be cleared by the filter when a new writer connects, -at which point the -filter will resume waiting for data to become available before -returning. -.It "BPF devices" -Returns when the BPF buffer is full, the BPF timeout has expired, or -when the BPF has -.Dq immediate mode -enabled and there is any data to read; -.Va data -contains the number of bytes available. -.It Eventfds -Returns when the counter is greater than 0; -.Va data -contains the counter value, which must be cast to -.Vt uint64_t . -.It Kqueues -Returns when pending events are present on the queue; -.Va data -contains the number of events available. -.El -.It Dv EVFILT_WRITE -Takes a descriptor as the identifier, and returns whenever -it is possible to write to the descriptor. -For sockets, pipes -and fifos, -.Va data -will contain the amount of space remaining in the write buffer. -The filter will set -.Dv EV_EOF -when the reader disconnects, and for the fifo case, this will be cleared -when a new reader connects. -Note that this filter is not supported for vnodes. -.Pp -For sockets, the low water mark and socket error handling is -identical to the -.Dv EVFILT_READ -case. -.Pp -For eventfds, -.Va data -will contain the maximum value that can be added to the counter -without blocking. -.Pp -For BPF devices, when the descriptor is attached to an interface the filter -always indicates that it is possible to write and -.Va data -will contain the MTU size of the underlying interface. -.It Dv EVFILT_EMPTY -Takes a descriptor as the identifier, and returns whenever -there is no remaining data in the write buffer. -.It Dv EVFILT_AIO -Events for this filter are not registered with -.Fn kevent -directly but are registered via the -.Va aio_sigevent -member of an asynchronous I/O request when it is scheduled via an -asynchronous I/O system call such as -.Fn aio_read . -The filter returns under the same conditions as -.Fn aio_error . -For more details on this filter see -.Xr sigevent 3 and -.Xr aio 4 . -.It Dv EVFILT_VNODE -Takes a file descriptor as the identifier and the events to watch for in -.Va fflags , -and returns when one or more of the requested events occurs on the descriptor. -The events to monitor are: -.Bl -tag -width "Dv NOTE_CLOSE_WRITE" -.It Dv NOTE_ATTRIB -The file referenced by the descriptor had its attributes changed. -.It Dv NOTE_CLOSE -A file descriptor referencing the monitored file, was closed. -The closed file descriptor did not have write access. -.It Dv NOTE_CLOSE_WRITE -A file descriptor referencing the monitored file, was closed. -The closed file descriptor had write access. -.Pp -This note, as well as -.Dv NOTE_CLOSE , -are not activated when files are closed forcibly by -.Xr unmount 2 or -.Xr revoke 2 . -Instead, -.Dv NOTE_REVOKE -is sent for such events. -.It Dv NOTE_DELETE -The -.Fn unlink -system call was called on the file referenced by the descriptor. -.It Dv NOTE_EXTEND -For regular file, the file referenced by the descriptor was extended. -.Pp -For directory, reports that a directory entry was added or removed, -as the result of rename operation. -The -.Dv NOTE_EXTEND -event is not reported when a name is changed inside the directory. -.It Dv NOTE_LINK -The link count on the file changed. -In particular, the -.Dv NOTE_LINK -event is reported if a subdirectory was created or deleted inside -the directory referenced by the descriptor. -.It Dv NOTE_OPEN -The file referenced by the descriptor was opened. -.It Dv NOTE_READ -A read occurred on the file referenced by the descriptor. -.It Dv NOTE_RENAME -The file referenced by the descriptor was renamed. -.It Dv NOTE_REVOKE -Access to the file was revoked via -.Xr revoke 2 -or the underlying file system was unmounted. -.It Dv NOTE_WRITE -A write occurred on the file referenced by the descriptor. -.El -.Pp -On return, -.Va fflags -contains the events which triggered the filter. -.It Dv EVFILT_PROC -Takes the process ID to monitor as the identifier and the events to watch for -in -.Va fflags , -and returns when the process performs one or more of the requested events. -If a process can normally see another process, it can attach an event to it. -The events to monitor are: -.Bl -tag -width "Dv NOTE_TRACKERR" -.It Dv NOTE_EXIT -The process has exited. -The exit status will be stored in -.Va data -in the same format as the status returned by -.Xr wait 2 . -.It Dv NOTE_FORK -The process has called -.Fn fork . -.It Dv NOTE_EXEC -The process has executed a new process via -.Xr execve 2 -or a similar call. -.It Dv NOTE_TRACK -Follow a process across -.Fn fork -calls. -The parent process registers a new kevent to monitor the child process -using the same -.Va fflags -as the original event. -The child process will signal an event with -.Dv NOTE_CHILD -set in -.Va fflags -and the parent PID in -.Va data . -.Pp -If the parent process fails to register a new kevent -.Pq usually due to resource limitations , -it will signal an event with -.Dv NOTE_TRACKERR -set in -.Va fflags , -and the child process will not signal a -.Dv NOTE_CHILD -event. -.El -.Pp -On return, -.Va fflags -contains the events which triggered the filter. -.It Dv EVFILT_PROCDESC -Takes the process descriptor created by -.Xr pdfork 2 -to monitor as the identifier and the events to watch for in -.Va fflags , -and returns when the associated process performs one or more of the -requested events. -The events to monitor are: -.Bl -tag -width "Dv NOTE_EXIT" -.It Dv NOTE_EXIT -The process has exited. -The exit status will be stored in -.Va data . -.El -.Pp -On return, -.Va fflags -contains the events which triggered the filter. -.It Dv EVFILT_SIGNAL -Takes the signal number to monitor as the identifier and returns -when the given signal is delivered to the process. -This coexists with the -.Fn signal -and -.Fn sigaction -facilities, and has a lower precedence. -The filter will record -all attempts to deliver a signal to a process, even if the signal has -been marked as -.Dv SIG_IGN , -except for the -.Dv SIGCHLD -signal, which, if ignored, will not be recorded by the filter. -Event notification happens after normal -signal delivery processing. -.Va data -returns the number of times the signal has occurred since the last call to -.Fn kevent . -This filter automatically sets the -.Dv EV_CLEAR -flag internally. -.It Dv EVFILT_TIMER -Establishes an arbitrary timer identified by -.Va ident . -When adding a timer, -.Va data -specifies the moment to fire the timer (for -.Dv NOTE_ABSTIME ) -or the timeout period. -The timer will be periodic unless -.Dv EV_ONESHOT -or -.Dv NOTE_ABSTIME -is specified. -On return, -.Va data -contains the number of times the timeout has expired since the last call to -.Fn kevent . -For non-monotonic timers, this filter automatically sets the -.Dv EV_CLEAR -flag internally. -.Pp -The filter accepts the following flags in the -.Va fflags -argument: -.Bl -tag -width "Dv NOTE_MSECONDS" -.It Dv NOTE_SECONDS -.Va data -is in seconds. -.It Dv NOTE_MSECONDS -.Va data -is in milliseconds. -.It Dv NOTE_USECONDS -.Va data -is in microseconds. -.It Dv NOTE_NSECONDS -.Va data -is in nanoseconds. -.It Dv NOTE_ABSTIME -The specified expiration time is absolute. -.El -.Pp -If -.Va fflags -is not set, the default is milliseconds. -On return, -.Va fflags -contains the events which triggered the filter. -.Pp -Periodic timers with a specified timeout of 0 will be silently adjusted to -timeout after 1 of the time units specified by the requested precision in -.Va fflags . -If an absolute time is specified that has already passed, then it is treated as -if the current time were specified and the event will fire as soon as possible. -.Pp -If an existing timer is re-added, the existing timer will be -effectively canceled (throwing away any undelivered record of previous -timer expiration) and re-started using the new parameters contained in -.Va data -and -.Va fflags . -.Pp -There is a system wide limit on the number of timers -which is controlled by the -.Va kern.kq_calloutmax -sysctl. -.It Dv EVFILT_USER -Establishes a user event identified by -.Va ident -which is not associated with any kernel mechanism but is triggered by -user level code. -The lower 24 bits of the -.Va fflags -may be used for user defined flags and manipulated using the following: -.Bl -tag -width "Dv NOTE_FFLAGSMASK" -.It Dv NOTE_FFNOP -Ignore the input -.Va fflags . -.It Dv NOTE_FFAND -Bitwise AND -.Va fflags . -.It Dv NOTE_FFOR -Bitwise OR -.Va fflags . -.It Dv NOTE_FFCOPY -Copy -.Va fflags . -.It Dv NOTE_FFCTRLMASK -Control mask for -.Va fflags . -.It Dv NOTE_FFLAGSMASK -User defined flag mask for -.Va fflags . -.El -.Pp -A user event is triggered for output with the following: -.Bl -tag -width "Dv NOTE_FFLAGSMASK" -.It Dv NOTE_TRIGGER -Cause the event to be triggered. -.El -.Pp -On return, -.Va fflags -contains the users defined flags in the lower 24 bits. -.El -.Sh CANCELLATION BEHAVIOUR -If -.Fa nevents -is non-zero, i.e., the function is potentially blocking, the call -is a cancellation point. -Otherwise, i.e., if -.Fa nevents -is zero, the call is not cancellable. -Cancellation can only occur before any changes are made to the kqueue, -or when the call was blocked and no changes to the queue were requested. -.Sh RETURN VALUES -The -.Fn kqueue -system call -creates a new kernel event queue and returns a file descriptor. -If there was an error creating the kernel event queue, a value of -1 is -returned and errno set. -.Pp -The -.Fn kevent -system call -returns the number of events placed in the -.Fa eventlist , -up to the value given by -.Fa nevents . -If an error occurs while processing an element of the -.Fa changelist -and there is enough room in the -.Fa eventlist , -then the event will be placed in the -.Fa eventlist -with -.Dv EV_ERROR -set in -.Va flags -and the system error in -.Va data . -Otherwise, -.Dv -1 -will be returned, and -.Dv errno -will be set to indicate the error condition. -If the time limit expires, then -.Fn kevent -returns 0. -.Sh EXAMPLES -.Bd -literal -compact -#include <sys/event.h> -#include <err.h> -#include <fcntl.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> - -int -main(int argc, char **argv) -{ - struct kevent event; /* Event we want to monitor */ - struct kevent tevent; /* Event triggered */ - int kq, fd, ret; - - if (argc != 2) - err(EXIT_FAILURE, "Usage: %s path\en", argv[0]); - fd = open(argv[1], O_RDONLY); - if (fd == -1) - err(EXIT_FAILURE, "Failed to open '%s'", argv[1]); - - /* Create kqueue. */ - kq = kqueue(); - if (kq == -1) - err(EXIT_FAILURE, "kqueue() failed"); - - /* Initialize kevent structure. */ - EV_SET(&event, fd, EVFILT_VNODE, EV_ADD | EV_CLEAR, NOTE_WRITE, - 0, NULL); - /* Attach event to the kqueue. */ - ret = kevent(kq, &event, 1, NULL, 0, NULL); - if (ret == -1) - err(EXIT_FAILURE, "kevent register"); - - for (;;) { - /* Sleep until something happens. */ - ret = kevent(kq, NULL, 0, &tevent, 1, NULL); - if (ret == -1) { - err(EXIT_FAILURE, "kevent wait"); - } else if (ret > 0) { - if (tevent.flags & EV_ERROR) - errx(EXIT_FAILURE, "Event error: %s", strerror(event.data)); - else - printf("Something was written in '%s'\en", argv[1]); - } - } - - /* kqueues are destroyed upon close() */ - (void)close(kq); - (void)close(fd); -} -.Ed -.Sh ERRORS -The -.Fn kqueue -system call fails if: -.Bl -tag -width Er -.It Bq Er ENOMEM -The kernel failed to allocate enough memory for the kernel queue. -.It Bq Er ENOMEM -The -.Dv RLIMIT_KQUEUES -rlimit -(see -.Xr getrlimit 2 ) -for the current user would be exceeded. -.It Bq Er EMFILE -The per-process descriptor table is full. -.It Bq Er ENFILE -The system file table is full. -.El -.Pp -The -.Fn kevent -system call fails if: -.Bl -tag -width Er -.It Bq Er EACCES -The process does not have permission to register a filter. -.It Bq Er EFAULT -There was an error reading or writing the -.Va kevent -structure. -.It Bq Er EBADF -The specified descriptor is invalid. -.It Bq Er EINTR -A signal was delivered before the timeout expired and before any -events were placed on the kqueue for return. -.It Bq Er EINTR -A cancellation request was delivered to the thread, but not yet handled. -.It Bq Er EINVAL -The specified time limit or filter is invalid. -.It Bq Er EINVAL -The specified length of the event or change lists is negative. -.It Bq Er ENOENT -The event could not be found to be modified or deleted. -.It Bq Er ENOMEM -No memory was available to register the event -or, in the special case of a timer, the maximum number of -timers has been exceeded. -This maximum is configurable via the -.Va kern.kq_calloutmax -sysctl. -.It Bq Er ESRCH -The specified process to attach to does not exist. -.El -.Pp -When -.Fn kevent -call fails with -.Er EINTR -error, all changes in the -.Fa changelist -have been applied. -.Sh SEE ALSO -.Xr aio_error 2 , -.Xr aio_read 2 , -.Xr aio_return 2 , -.Xr poll 2 , -.Xr read 2 , -.Xr select 2 , -.Xr sigaction 2 , -.Xr write 2 , -.Xr pthread_setcancelstate 3 , -.Xr signal 3 -.Rs -.%A Jonathan Lemon -.%T "Kqueue: A Generic and Scalable Event Notification Facility" -.%I USENIX Association -.%B Proceedings of the FREENIX Track: 2001 USENIX Annual Technical Conference -.%D June 25-30, 2001 -.\".http://www.usenix.org/event/usenix01/freenix01/full_papers/lemon/lemon.pdf -.Re -.Sh HISTORY -The -.Fn kqueue -and -.Fn kevent -system calls first appeared in -.Fx 4.1 . -.Sh AUTHORS -The -.Fn kqueue -system and this manual page were written by -.An Jonathan Lemon Aq Mt jlemon@FreeBSD.org . -.Sh BUGS -.Pp -In versions older than -.Fx 12.0 , -.In sys/event.h -failed to parse without including -.In sys/types.h -manually. |