Built-In Variables

The following table provides a complete list of D built-in variables. All of these variables are scalar global variables; no thread-local or clause-local variables or built-in associative arrays are currently defined by D.

Table 2-12 DTrace Built-In Variables

Variable	Description
int64_t arg0, ..., arg9	The first 10 input arguments to a probe represented as raw 64-bit integers. If fewer than 10 arguments are passed to the current probe, the remaining variables return zero.
args[]	The typed arguments to the current probe, if any. The args[] array is accessed using an integer index, but each element is defined to be the type corresponding to the given probe argument. For example consider the start probe in the io provider. In this probe, args[0] is of type bufinfo_t struct, args[1] is of type devinfo_t struct and args[2] is of type fileinfo_t struct.
uintptr_t caller	The program counter location that called the current kernel thread, at the time the probe fired.
uintptr_t ucaller	The program counter location that called the current user-level thread, at the time the probe fired.
chipid_t chip	The CPU chip identifier for the current physical chip. For more information, see sched Provider.
processorid_t cpu	The CPU identifier for the current CPU. For more information, see sched Provider.
cpuinfo_t *curcpu	The CPU information for the current CPU. For more information, see sched Provider.
lwpsinfo_t *curlwpsinfo	The lightweight process (LWP) state of the LWP associated with the current thread. This structure is described in further detail in the proc man page.
psinfo_t *curpsinfo	The process state of the process associated with the current thread. This structure is described in further detail in the proc man page.
kthread_t *curthread	The address of the operating system kernel's internal data structure for the current thread, the kthread_t. The kthread_t is defined in <sys/thread.h>.
string cwd	The name of the current working directory of the process associated with the current thread.
uint_t epid	The enabled probe ID (EPID) for the current probe. This integer uniquely identifies a particular probe that is enabled with a specific predicate and set of actions.
int errno	The error value returned by the last system call executed by this thread.
string execname	The name that was passed to exec to execute the current process.
gid_t gid	The real group ID of the current process.
uint_t id	The probe ID for the current probe. This ID is the system-wide unique identifier for the probe as published by DTrace and listed in the output of dtrace -l.
uint_t ipl	The interrupt priority level (IPL) on the current CPU at probe firing time.
lgrp_id_t lgrp	The latency group ID for the latency group of which the current CPU is a member. See sched Provider for more information.
pid_t pid	The process ID of the current process.
pid_t ppid	The parent process ID of the current process.
string probefunc	The function name portion of the current probe's description.
string probemod	The module name portion of the current probe's description.
string probename	The name portion of the current probe's description.
string probeprov	The provider name portion of the current probe's description.
psetid_t pset	The processor set ID for the processor set containing the current CPU. See sched Provider for more information.
string root	The name of the root directory of the process associated with the current thread.
string kthreadname	The kernel thread name associated with the currently executing thread.
string uthreadname	The user thread name associated with the currently executing thread.
uint_t stackdepth	The current thread's stack frame depth at probe firing time.
id_t tid	The thread ID of the current thread. For threads associated with user processes, this value is equal to the result of a call to pthread_self. For more information, see the pthread_self(3C) man page.
uint64_t timestamp	The current value of a nanosecond timestamp counter. This counter increments from an arbitrary point in the past and should only be used for relative computations.
uid_t uid	The real user ID of the current process.
uint64_t uregs[]	The current thread's saved user-mode register values at probe firing time. For information about the use of the uregs[] array, see User Process Tracing.
uint64_t vtimestamp	The current value of a nanosecond timestamp counter that is virtualized to the amount of time that the current thread has been running on a CPU, minus the time spent in DTrace predicates and actions. This counter increments from an arbitrary point in the past and should only be used for relative time computations.
uint64_t walltimestamp	The current number of nanoseconds since 00:00 Universal Coordinated Time, January 1, 1970.
uint_t dtrace_is_tracing	Contains non-zero if the current thread is being traced by the current DTrace consumer.
string zonename	Name of the zone as specified on creation of the process.
zoneid_t zoneid	The zone identifier.

For information about functions built into the D language such as trace, see DTrace Actions and Subroutines.