Cross-platform system configuration values.
val argv : string array
The command line arguments given to the process. The first element is the command name used to invoke the program. The following elements are the command-line arguments given to the program.
val interactive : bool Pervasives.ref
interactive
is set to true
when being executed in the ocaml
REPL, and false
otherwise.
val os_type : string
os_type
describes the operating system that the OCaml program is running on. Its
value is one of "Unix"
, "Win32"
, or "Cygwin"
.
Currently, the official distribution only supports Native
and Bytecode
,
but it can be other backends with alternative compilers, for example,
JavaScript.
val word_size_in_bits : int
word_size_in_bits
is the number of bits in one word on the machine currently
executing the OCaml program. Generally speaking it will be either 32
or 64
.
val int_size_in_bits : int
int_size_in_bits
is the number of bits in the int
type. Generally, on 32-bit
platforms, its value will be 31
, and on 64 bit platforms its value will be 63
.
When running in JavaScript, it will be 32
.
val runtime_variant : unit ‑> string
Returns the name of the runtime variant the program is running on. This is normally
the argument given to -runtime-variant
at compile time, but for byte-code it can be
changed after compilation.
val runtime_parameters : unit ‑> string
Returns the value of the runtime parameters, in the same format as the contents of the
OCAMLRUNPARAM
environment variable.
val ocaml_version : string
ocaml_version
is the OCaml version with which the program was compiled. It is a
string of the form "major.minor[.patchlevel][+additional-info]"
, where major, minor,
and patchlevel are integers, and additional-info is an arbitrary string. The
[.patchlevel]
and [+additional-info]
parts may be absent.
val enable_runtime_warnings : bool ‑> unit
Controls whether the OCaml runtime system can emit warnings on stderr. Currently, the
only supported warning is triggered when a channel created by open_*
functions is
finalized without being closed. Runtime warnings are enabled by default.
val opaque_identity : 'a ‑> 'a
For the purposes of optimization, opaque_identity
behaves like an unknown (and thus
possibly side-effecting) function. At runtime, opaque_identity
disappears
altogether. A typical use of this function is to prevent pure computations from being
optimized away in benchmarking loops. For example:
for _round = 1 to 100_000 do
ignore (Sys.opaque_identity (my_pure_computation ()))
done