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)