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CAP_IOCTLS_LIMIT(2)	  FreeBSD System Calls Manual	   CAP_IOCTLS_LIMIT(2)

NAME
     cap_ioctls_limit, cap_ioctls_get -- manage	allowed	ioctl commands

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <sys/capability.h>

     int
     cap_ioctls_limit(int fd, const unsigned long *cmds, size_t	ncmds);

     ssize_t
     cap_ioctls_get(int	fd, unsigned long *cmds, size_t	maxcmds);

DESCRIPTION
     If	a file descriptor is granted the CAP_IOCTL capability right, the list
     of	allowed	ioctl(2) commands can be selectively reduced (but never
     expanded) with the	cap_ioctls_limit() system call.	 The cmds argument is
     an	array of ioctl(2) commands and the ncmds argument specifies the	number
     of	elements in the	array.	There can be up	to 256 elements	in the array.

     The list of allowed ioctl commands	for a given file descriptor can	be
     obtained with the cap_ioctls_get()	system call.  The cmds argument	points
     at	memory that can	hold up	to maxcmds values.  The	function populates the
     provided buffer with up to	maxcmds	elements, but always returns the total
     number of ioctl commands allowed for the given file descriptor.  The
     total number of ioctls commands for the given file	descriptor can be
     obtained by passing NULL as the cmds argument and 0 as the	maxcmds	argu-
     ment.  If all ioctl commands are allowed (CAP_IOCTL capability right is
     assigned to the file descriptor and the cap_ioctls_limit()	system call
     was never called for this file descriptor), the cap_ioctls_get() system
     call will return CAP_IOCTLS_ALL and won't modify the buffer pointed to by
     the cmds argument.

RETURN VALUES
     The cap_ioctls_limit() function returns the value 0 if successful;	other-
     wise the value -1 is returned and the global variable errno is set	to
     indicate the error.

     The cap_ioctls_get() function, if successful, returns the total number of
     allowed ioctl commands or the value CAP_IOCTLS_ALL	if all ioctls commands
     are allowed.  On failure the value	-1 is returned and the global variable
     errno is set to indicate the error.

ERRORS
     cap_ioctls_limit()	succeeds unless:

     [EBADF]		The fd argument	is not a valid descriptor.

     [EFAULT]		The cmds argument points at an invalid address.

     [EINVAL]		The ncmds argument is greater than 256.

     [ENOTCAPABLE]	cmds would expand the list of allowed ioctl(2) com-
			mands.

     cap_ioctls_get() succeeds unless:

     [EBADF]		The fd argument	is not a valid descriptor.

     [EFAULT]		The cmds argument points at invalid address.

SEE ALSO
     cap_fcntls_limit(2), cap_rights_limit(2), ioctl(2)

HISTORY
     Support for capabilities and capabilities mode was	developed as part of
     the TrustedBSD Project.

AUTHORS
     This function was created by Pawel	Jakub Dawidek <pawel@dawidek.net>
     under sponsorship of the FreeBSD Foundation.

FreeBSD	10.0		      September	20, 2012		  FreeBSD 10.0

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | HISTORY | AUTHORS

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