FSETOWN(9) | Kernel Developer's Manual | FSETOWN(9) |
fsetown
, fgetown
,
fownsignal
—
#include <sys/file.h>
int
fsetown
(struct
lwp *l, pid_t
*pgid, int cmd,
const void *data);
int
fgetown
(struct
lwp *l, pid_t pgid,
int cmd,
void *data);
void
fownsignal
(pid_t
pgid, int signo,
int code,
int band,
void *fdescdata);
fsetown
() sets the owner of file.
cmd is an ioctl command, one of
SIOCSPGRP
, FIOSETOWN
, and
TIOCSPGRP
. data is interpreted
as a pointer to a signed integer, the integer being the ID of the owner. The
cmd determines how exactly data
should be interpreted. If cmd is
TIOCSPGRP
, the ID needs to be positive and is
interpreted as process group ID. For SIOCSPGRP
and
FIOSETOWN
, the passed ID is the process ID if
positive, or the process group ID if negative.
fgetown
() returns the current owner of the
file. cmd is an ioctl command, one of
SIOCGPGRP
, FIOGETOWN
, and
TIOCGPGRP
. data is interpreted
as a pointer to a signed integer, and the value is set according to the
passed cmd. For TIOCGPGRP
, the
returned data value is positive process group ID if
the owner is the process group, or negative process ID if the owner is a
process. For other ioctls, the returned value is the positive process ID if
the owner is a process, or the negative process group ID if the owner is a
process group.
fownsignal
() schedules the
signo signal to be sent to the current file descriptor
owner. The signals typically used with this function are
SIGIO
and SIGURG
. The
code and band arguments are sent
along with the signal as additional signal specific information if
SA_SIGINFO
is activated. If the information is not
available from the context of the fownsignal
() call,
these should be passed as zero. fdescdata is used to
lookup the file descriptor for SA_SIGINFO
signals.
If it is specified, the file descriptor number is sent along with the signal
as additional signal specific information. If file descriptor data pointer
is not available in the context of the fownsignal
()
call, NULL
should be used instead.
Note that a fcntl(2)
F_SETOWN request
is translated by the kernel to a
FIOSETOWN
ioctl, and
F_GETOWN
is translated to
FIOGETOWN
. This is done transparently by generic
code, before the device- or subsystem-specific ioctl entry function is
called.
December 20, 2005 | NetBSD 9.0 |