1Stdlib.Sys(3) OCaml library Stdlib.Sys(3)
2
6 Stdlib.Sys - no description
7
9 Module Stdlib.Sys
10
12 Module Sys
13 : (module Stdlib__sys)
14 val argv : string array
23 The command line arguments given to the process. The first element is
25 the command name used to invoke the program. The following elements
26 are the command-line arguments given to the program.
27 val executable_name : string
31 The name of the file containing the executable currently running. This
33 name may be absolute or relative to the current directory, depending on
34 the platform and whether the program was compiled to bytecode or a
35 native executable.
36 val file_exists : string -> bool
40 Test if a file with the given name exists.
42 val is_directory : string -> bool
46 Returns true if the given name refers to a directory, false if it
48 refers to another kind of file. Raise Sys_error if no file exists with
49 the given name.
50 Since 3.10.0
53 val remove : string -> unit
57 Remove the given file name from the file system.
59 val rename : string -> string -> unit
63 Rename a file. rename oldpath newpath renames the file called oldpath
65 , giving it newpath as its new name, moving it between directories if
66 needed. If newpath already exists, its contents will be replaced with
67 those of oldpath . Depending on the operating system, the metadata
68 (permissions, owner, etc) of newpath can either be preserved or be
69 replaced by those of oldpath .
70 Since 4.06 concerning the "replace existing file" behavior
73 val getenv : string -> string
77 Return the value associated to a variable in the process environment.
79 Raise Not_found if the variable is unbound.
80 val getenv_opt : string -> string option
84 Return the value associated to a variable in the process environment or
86 None if the variable is unbound.
87 Since 4.05
90 val command : string -> int
94 Execute the given shell command and return its exit code.
96 val time : unit -> float
100 Return the processor time, in seconds, used by the program since the
102 beginning of execution.
103 val chdir : string -> unit
107 Change the current working directory of the process.
109 val getcwd : unit -> string
113 Return the current working directory of the process.
115 val readdir : string -> string array
119 Return the names of all files present in the given directory. Names
121 denoting the current directory and the parent directory ( . and .. in
122 Unix) are not returned. Each string in the result is a file name
123 rather than a complete path. There is no guarantee that the name
124 strings in the resulting array will appear in any specific order; they
125 are not, in particular, guaranteed to appear in alphabetical order.
126 val interactive : bool ref
130 This reference is initially set to false in standalone programs and to
132 true if the code is being executed under the interactive toplevel sys‐
133 tem ocaml .
134 val os_type : string
138 Operating system currently executing the OCaml program. One of
140 - Unix (for all Unix versions, including Linux and Mac OS X),
142 - Win32 (for MS-Windows, OCaml compiled with MSVC++ or Mingw),
144 - Cygwin (for MS-Windows, OCaml compiled with Cygwin).
146 type backend_type =
150 | Native
151 | Bytecode
152 | Other of string
153 Currently, the official distribution only supports Native and Bytecode
156 , but it can be other backends with alternative compilers, for example,
157 javascript.
158 Since 4.04.0
161 val backend_type : backend_type
165 Backend type currently executing the OCaml program.
167 Since 4.04.0
170 val unix : bool
174 True if Sys.os_type = Unix .
176 Since 4.01.0
179 val win32 : bool
183 True if Sys.os_type = Win32 .
185 Since 4.01.0
188 val cygwin : bool
192 True if Sys.os_type = Cygwin .
194 Since 4.01.0
197 val word_size : int
201 Size of one word on the machine currently executing the OCaml program,
203 in bits: 32 or 64.
204 val int_size : int
208 Size of int , in bits. It is 31 (resp. 63) when using OCaml on a 32-bit
210 (resp. 64-bit) platform. It may differ for other implementations, e.g.
211 it can be 32 bits when compiling to JavaScript.
212 Since 4.03.0
215 val big_endian : bool
219 Whether the machine currently executing the Caml program is big-endian.
221 Since 4.00.0
224 val max_string_length : int
228 Maximum length of strings and byte sequences.
230 val max_array_length : int
234 Maximum length of a normal array (i.e. any array whose elements are not
236 of type float ). The maximum length of a float array is max_floatar‐
237 ray_length if OCaml was configured with --enable-flat-float-array and
238 max_array_length if configured with --disable-flat-float-array .
239 val max_floatarray_length : int
243 Maximum length of a floatarray. This is also the maximum length of a
245 float array when OCaml is configured with --enable-flat-float-array .
246 val runtime_variant : unit -> string
250 Return the name of the runtime variant the program is running on. This
252 is normally the argument given to -runtime-variant at compile time, but
253 for byte-code it can be changed after compilation.
254 Since 4.03.0
257 val runtime_parameters : unit -> string
261 Return the value of the runtime parameters, in the same format as the
263 contents of the OCAMLRUNPARAM environment variable.
264 Since 4.03.0
267 Signal handling
272 type signal_behavior =
273 | Signal_default
274 | Signal_ignore
275 | Signal_handle of (int -> unit)
276 What to do when receiving a signal:
279 - Signal_default : take the default behavior (usually: abort the pro‐
281 gram)
282 - Signal_ignore : ignore the signal
284 - Signal_handle f : call function f , giving it the signal number as
286 argument.
287 val signal : int -> signal_behavior -> signal_behavior
292 Set the behavior of the system on receipt of a given signal. The first
294 argument is the signal number. Return the behavior previously associ‐
295 ated with the signal. If the signal number is invalid (or not available
296 on your system), an Invalid_argument exception is raised.
297 val set_signal : int -> signal_behavior -> unit
301 Same as Sys.signal but return value is ignored.
303 Signal numbers for the standard POSIX signals.
308 val sigabrt : int
309 Abnormal termination
311 val sigalrm : int
315 Timeout
317 val sigfpe : int
321 Arithmetic exception
323 val sighup : int
327 Hangup on controlling terminal
329 val sigill : int
333 Invalid hardware instruction
335 val sigint : int
339 Interactive interrupt (ctrl-C)
341 val sigkill : int
345 Termination (cannot be ignored)
347 val sigpipe : int
351 Broken pipe
353 val sigquit : int
357 Interactive termination
359 val sigsegv : int
363 Invalid memory reference
365 val sigterm : int
369 Termination
371 val sigusr1 : int
375 Application-defined signal 1
377 val sigusr2 : int
381 Application-defined signal 2
383 val sigchld : int
387 Child process terminated
389 val sigcont : int
393 Continue
395 val sigstop : int
399 Stop
401 val sigtstp : int
405 Interactive stop
407 val sigttin : int
411 Terminal read from background process
413 val sigttou : int
417 Terminal write from background process
419 val sigvtalrm : int
423 Timeout in virtual time
425 val sigprof : int
429 Profiling interrupt
431 val sigbus : int
435 Bus error
437 Since 4.03
440 val sigpoll : int
444 Pollable event
446 Since 4.03
449 val sigsys : int
453 Bad argument to routine
455 Since 4.03
458 val sigtrap : int
462 Trace/breakpoint trap
464 Since 4.03
467 val sigurg : int
471 Urgent condition on socket
473 Since 4.03
476 val sigxcpu : int
480 Timeout in cpu time
482 Since 4.03
485 val sigxfsz : int
489 File size limit exceeded
491 Since 4.03
494 exception Break
498 Exception raised on interactive interrupt if Sys.catch_break is on.
501 val catch_break : bool -> unit
505 catch_break governs whether interactive interrupt (ctrl-C) terminates
508 the program or raises the Break exception. Call catch_break true to
509 enable raising Break , and catch_break false to let the system termi‐
510 nate the program on user interrupt.
511 val ocaml_version : string
515 ocaml_version is the version of OCaml. It is a string of the form
518 major.minor[.patchlevel][+additional-info] , where major , minor , and
519 patchlevel are integers, and additional-info is an arbitrary string.
520 The [.patchlevel] and [+additional-info] parts may be absent.
521 val enable_runtime_warnings : bool -> unit
525 Control whether the OCaml runtime system can emit warnings on stderr.
527 Currently, the only supported warning is triggered when a channel cre‐
528 ated by open_* functions is finalized without being closed. Runtime
529 warnings are enabled by default.
530 Since 4.03.0
533 val runtime_warnings_enabled : unit -> bool
537 Return whether runtime warnings are currently enabled.
539 Since 4.03.0
542 Optimization
547 val opaque_identity : 'a -> 'a
548 For the purposes of optimization, opaque_identity behaves like an
550 unknown (and thus possibly side-effecting) function.
551 At runtime, opaque_identity disappears altogether.
553 A typical use of this function is to prevent pure computations from
555 being optimized away in benchmarking loops. For example: for _round =
556 1 to 100_000 do ignore (Sys.opaque_identity (my_pure_computation ()))
557 done
558 Since 4.03.0
562OCamldoc 2019-07-30 Stdlib.Sys(3)