p_cansee(9) [freebsd man page]

P_CANSEE(9)						   BSD Kernel Developer's Manual					       P_CANSEE(9)

NAME

     p_cansee -- determine visibility of a process

SYNOPSIS

     #include <sys/param.h>
     #include <sys/proc.h>

     int
     p_cansee(struct thread *td, struct proc *p);

DESCRIPTION

     This function can be used to determine if a given process p is visible to the thread td, where the notion of ``visibility'' may be read as
     ``awareness of existence''.

     The function is implemented using cr_cansee(9), and the dependencies on sysctl(8) variables documented in the cr_cansee(9) manual page apply.

RETURN VALUES

     The p_cansee() function returns 0 if the process denoted by p is visible by thread td, or a non-zero error return value otherwise.

ERRORS

     [ESRCH]		Process p is not visible to thread td as determined by cr_cansee(9).

     [ESRCH]		Thread td has been jailed and process p does not belong to the same jail as td.

     [ESRCH]		The MAC subsystem denied visibility.

SEE ALSO

     jail(2), sysctl(8), cr_cansee(9), mac(9), p_candebug(9), prison_check(9)

BSD
								 November 19, 2006							       BSD

CR_CANSEE(9)						   BSD Kernel Developer's Manual					      CR_CANSEE(9)

NAME

     cr_cansee -- determine visibility of objects given their user credentials

SYNOPSIS

     #include <sys/param.h>
     #include <sys/systm.h>
     #include <sys/ucred.h>

     int
     cr_cansee(struct ucred *u1, struct ucred *u2);

DESCRIPTION

     This function determines the visibility of objects in the kernel based on the real user IDs and group IDs in the credentials u1 and u2 asso-
     ciated with them.

     The visibility of objects is influenced by the sysctl(8) variables security.bsd.see_other_gids and security.bsd.see_other_uids, as per the
     description in cr_seeothergids(9) and cr_seeotheruids(9) respectively.

RETURN VALUES

     This function returns zero if the object with credential u1 can ``see'' the object with credential u2, or ESRCH otherwise.

ERRORS

     [ESRCH]		The object with credential u1 cannot ``see'' the object with credential u2.

     [ESRCH]		The object with credential u1 has been jailed and the object with credential u2 does not belong to the same jail as u1.

     [ESRCH]		The MAC subsystem denied visibility.

SEE ALSO

     cr_seeothergids(9), cr_seeotheruids(9), mac(9), p_cansee(9)

BSD
								 November 19, 2006							       BSD