Vários testes proc possuem um argumento do tipo psinfo_t, uma estrutura documentada em proc(4). A definição da estrutura de psinfo_t conforme disponível aos consumidores do DTrace é a seguinte:
typedef struct psinfo {
int pr_nlwp; /* number of active lwps in the process */
pid_t pr_pid; /* unique process id */
pid_t pr_ppid; /* process id of parent */
pid_t pr_pgid; /* pid of process group leader */
pid_t pr_sid; /* session id */
uid_t pr_uid; /* real user id */
uid_t pr_euid; /* effective user id */
gid_t pr_gid; /* real group id */
gid_t pr_egid; /* effective group id */
uintptr_t pr_addr; /* address of process */
dev_t pr_ttydev; /* controlling tty device (or PRNODEV) */
timestruc_t pr_start; /* process start time, from the epoch */
char pr_fname[PRFNSZ]; /* name of execed file */
char pr_psargs[PRARGSZ]; /* initial characters of arg list */
int pr_argc; /* initial argument count */
uintptr_t pr_argv; /* address of initial argument vector */
uintptr_t pr_envp; /* address of initial environment vector */
char pr_dmodel; /* data model of the process */
taskid_t pr_taskid; /* task id */
projid_t pr_projid; /* project id */
poolid_t pr_poolid; /* pool id */
zoneid_t pr_zoneid; /* zone id */
} psinfo_t;
O campo pr_dmodel é definido como PR_MODEL_ILP32 , indicando um processo de 32 bits, ou PR_MODEL_LP64, indicando um processo de 64 bits.