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 na‐
35 tive 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.
49 Since 3.10.0
52 Raises Sys_error if no file exists with the given name.
55 val remove : string -> unit
59 Remove the given file name from the file system.
61 val rename : string -> string -> unit
65 Rename a file. rename oldpath newpath renames the file called oldpath
67 , giving it newpath as its new name, moving it between directories if
68 needed. If newpath already exists, its contents will be replaced with
69 those of oldpath . Depending on the operating system, the metadata
70 (permissions, owner, etc) of newpath can either be preserved or be re‐
71 placed by those of oldpath .
72 Since 4.06 concerning the "replace existing file" behavior
75 val getenv : string -> string
79 Return the value associated to a variable in the process environment.
81 Raises Not_found if the variable is unbound.
84 val getenv_opt : string -> string option
88 Return the value associated to a variable in the process environment or
90 None if the variable is unbound.
91 Since 4.05
94 val command : string -> int
98 Execute the given shell command and return its exit code.
100 The argument of Sys.command is generally the name of a command followed
102 by zero, one or several arguments, separated by whitespace. The given
103 argument is interpreted by a shell: either the Windows shell cmd.exe
104 for the Win32 ports of OCaml, or the POSIX shell sh for other ports.
105 It can contain shell builtin commands such as echo , and also special
106 characters such as file redirections > and < , which will be honored by
107 the shell.
108 Conversely, whitespace or special shell characters occurring in command
110 names or in their arguments must be quoted or escaped so that the shell
111 does not interpret them. The quoting rules vary between the POSIX
112 shell and the Windows shell. The Filename.quote_command performs the
113 appropriate quoting given a command name, a list of arguments, and op‐
114 tional file redirections.
115 val time : unit -> float
119 Return the processor time, in seconds, used by the program since the
121 beginning of execution.
122 val chdir : string -> unit
126 Change the current working directory of the process.
128 val mkdir : string -> int -> unit
132 Create a directory with the given permissions.
134 Since 4.12.0
137 val rmdir : string -> unit
141 Remove an empty directory.
143 Since 4.12.0
146 val getcwd : unit -> string
150 Return the current working directory of the process.
152 val readdir : string -> string array
156 Return the names of all files present in the given directory. Names
158 denoting the current directory and the parent directory ( "." and ".."
159 in Unix) are not returned. Each string in the result is a file name
160 rather than a complete path. There is no guarantee that the name
161 strings in the resulting array will appear in any specific order; they
162 are not, in particular, guaranteed to appear in alphabetical order.
163 val interactive : bool ref
167 This reference is initially set to false in standalone programs and to
169 true if the code is being executed under the interactive toplevel sys‐
170 tem ocaml .
171 val os_type : string
175 Operating system currently executing the OCaml program. One of
177 - "Unix" (for all Unix versions, including Linux and Mac OS X),
179 - "Win32" (for MS-Windows, OCaml compiled with MSVC++ or Mingw),
181 - "Cygwin" (for MS-Windows, OCaml compiled with Cygwin).
183 type backend_type =
187 | Native
188 | Bytecode
189 | Other of string
190 Currently, the official distribution only supports Native and Bytecode
193 , but it can be other backends with alternative compilers, for example,
194 javascript.
195 Since 4.04.0
198 val backend_type : backend_type
202 Backend type currently executing the OCaml program.
204 Since 4.04.0
207 val unix : bool
211 True if Sys.os_type = "Unix" .
213 Since 4.01.0
216 val win32 : bool
220 True if Sys.os_type = "Win32" .
222 Since 4.01.0
225 val cygwin : bool
229 True if Sys.os_type = "Cygwin" .
231 Since 4.01.0
234 val word_size : int
238 Size of one word on the machine currently executing the OCaml program,
240 in bits: 32 or 64.
241 val int_size : int
245 Size of int , in bits. It is 31 (resp. 63) when using OCaml on a 32-bit
247 (resp. 64-bit) platform. It may differ for other implementations, e.g.
248 it can be 32 bits when compiling to JavaScript.
249 Since 4.03.0
252 val big_endian : bool
256 Whether the machine currently executing the Caml program is big-endian.
258 Since 4.00.0
261 val max_string_length : int
265 Maximum length of strings and byte sequences.
267 val max_array_length : int
271 Maximum length of a normal array (i.e. any array whose elements are not
273 of type float ). The maximum length of a float array is max_floatar‐
274 ray_length if OCaml was configured with --enable-flat-float-array and
275 max_array_length if configured with --disable-flat-float-array .
276 val max_floatarray_length : int
280 Maximum length of a floatarray. This is also the maximum length of a
282 float array when OCaml is configured with --enable-flat-float-array .
283 val runtime_variant : unit -> string
287 Return the name of the runtime variant the program is running on. This
289 is normally the argument given to -runtime-variant at compile time, but
290 for byte-code it can be changed after compilation.
291 Since 4.03.0
294 val runtime_parameters : unit -> string
298 Return the value of the runtime parameters, in the same format as the
300 contents of the OCAMLRUNPARAM environment variable.
301 Since 4.03.0
304 Signal handling
309 type signal_behavior =
310 | Signal_default
311 | Signal_ignore
312 | Signal_handle of (int -> unit)
313 What to do when receiving a signal:
316 - Signal_default : take the default behavior (usually: abort the pro‐
318 gram)
319 - Signal_ignore : ignore the signal
321 - Signal_handle f : call function f , giving it the signal number as
323 argument.
324 val signal : int -> signal_behavior -> signal_behavior
329 Set the behavior of the system on receipt of a given signal. The first
331 argument is the signal number. Return the behavior previously associ‐
332 ated with the signal. If the signal number is invalid (or not available
333 on your system), an Invalid_argument exception is raised.
334 val set_signal : int -> signal_behavior -> unit
338 Same as Sys.signal but return value is ignored.
340 Signal numbers for the standard POSIX signals.
345 val sigabrt : int
346 Abnormal termination
348 val sigalrm : int
352 Timeout
354 val sigfpe : int
358 Arithmetic exception
360 val sighup : int
364 Hangup on controlling terminal
366 val sigill : int
370 Invalid hardware instruction
372 val sigint : int
376 Interactive interrupt (ctrl-C)
378 val sigkill : int
382 Termination (cannot be ignored)
384 val sigpipe : int
388 Broken pipe
390 val sigquit : int
394 Interactive termination
396 val sigsegv : int
400 Invalid memory reference
402 val sigterm : int
406 Termination
408 val sigusr1 : int
412 Application-defined signal 1
414 val sigusr2 : int
418 Application-defined signal 2
420 val sigchld : int
424 Child process terminated
426 val sigcont : int
430 Continue
432 val sigstop : int
436 Stop
438 val sigtstp : int
442 Interactive stop
444 val sigttin : int
448 Terminal read from background process
450 val sigttou : int
454 Terminal write from background process
456 val sigvtalrm : int
460 Timeout in virtual time
462 val sigprof : int
466 Profiling interrupt
468 val sigbus : int
472 Bus error
474 Since 4.03
477 val sigpoll : int
481 Pollable event
483 Since 4.03
486 val sigsys : int
490 Bad argument to routine
492 Since 4.03
495 val sigtrap : int
499 Trace/breakpoint trap
501 Since 4.03
504 val sigurg : int
508 Urgent condition on socket
510 Since 4.03
513 val sigxcpu : int
517 Timeout in cpu time
519 Since 4.03
522 val sigxfsz : int
526 File size limit exceeded
528 Since 4.03
531 exception Break
535 Exception raised on interactive interrupt if Sys.catch_break is on.
538 val catch_break : bool -> unit
542 catch_break governs whether interactive interrupt (ctrl-C) terminates
545 the program or raises the Break exception. Call catch_break true to
546 enable raising Break , and catch_break false to let the system termi‐
547 nate the program on user interrupt.
548 val ocaml_version : string
552 ocaml_version is the version of OCaml. It is a string of the form "ma‐
555 jor.minor[.patchlevel][(+|~)additional-info]" , where major , minor ,
556 and patchlevel are integers, and additional-info is an arbitrary
557 string. The [.patchlevel] part is absent for versions anterior to
558 3.08.0. The [(+|~)additional-info] part may be absent.
559 val enable_runtime_warnings : bool -> unit
563 Control whether the OCaml runtime system can emit warnings on stderr.
565 Currently, the only supported warning is triggered when a channel cre‐
566 ated by open_* functions is finalized without being closed. Runtime
567 warnings are disabled by default.
568 Since 4.03.0
571 val runtime_warnings_enabled : unit -> bool
575 Return whether runtime warnings are currently enabled.
577 Since 4.03.0
580 Optimization
585 val opaque_identity : 'a -> 'a
586 For the purposes of optimization, opaque_identity behaves like an un‐
588 known (and thus possibly side-effecting) function.
589 At runtime, opaque_identity disappears altogether.
591 A typical use of this function is to prevent pure computations from be‐
593 ing optimized away in benchmarking loops. For example:
594 for _round = 1 to 100_000 do
595 ignore (Sys.opaque_identity (my_pure_computation ()))
596 done
597 Since 4.03.0
601 module Immediate64 : sig end
604OCamldoc 2022-02-04 Stdlib.Sys(3)