1Thread(3)                        OCaml library                       Thread(3)
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NAME

6       Thread - Lightweight threads for Posix 1003.1c and Win32.
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Module

9       Module   Thread
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Documentation

12       Module Thread
13        : sig end
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16       Lightweight threads for Posix 1003.1c and Win32.
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22       type t
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25       The type of thread handles.
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30   Thread creation and termination
31       val create : ('a -> 'b) -> 'a -> t
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34       Thread.create  funct  arg creates a new thread of control, in which the
35       function application funct arg is executed concurrently with the  other
36       threads  of  the program.  The application of Thread.create returns the
37       handle of the newly created thread.  The new thread terminates when the
38       application  funct  arg  returns,  either  normally  or  by  raising an
39       uncaught exception.  In the latter case, the exception  is  printed  on
40       standard  error,  but  not  propagated back to the parent thread. Simi‐
41       larly, the result of the application funct arg  is  discarded  and  not
42       directly accessible to the parent thread.
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46       val self : unit -> t
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48       Return the thread currently executing.
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52       val id : t -> int
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54       Return  the  identifier  of the given thread. A thread identifier is an
55       integer that identifies uniquely the thread.  It can be used  to  build
56       data structures indexed by threads.
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60       val exit : unit -> unit
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62       Terminate prematurely the currently executing thread.
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66       val kill : t -> unit
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68       Terminate prematurely the thread whose handle is given.
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73   Suspending threads
74       val delay : float -> unit
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77       delay d suspends the execution of the calling thread for d seconds. The
78       other program threads continue to run during this time.
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82       val join : t -> unit
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85       join th suspends the execution of the calling thread until  the  thread
86       th has terminated.
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90       val wait_read : Unix.file_descr -> unit
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92       See Thread.wait_write .
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96       val wait_write : Unix.file_descr -> unit
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98       This function does nothing in this implementation.
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102       val wait_timed_read : Unix.file_descr -> float -> bool
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104       See Thread.wait_timed_write .
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108       val wait_timed_write : Unix.file_descr -> float -> bool
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110       Suspend  the execution of the calling thread until at least one charac‐
111       ter or EOF is available for reading ( wait_read ) or one character  can
112       be  written  without  blocking  (  wait_write  ) on the given Unix file
113       descriptor. Wait for at most the amount of time given as  second  argu‐
114       ment  (in  seconds).   Return  true if the file descriptor is ready for
115       input/output and false if the timeout expired.
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117       These functions return immediately true in the Win32 implementation.
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121       val  select  :  Unix.file_descr  list  ->   Unix.file_descr   list   ->
122       Unix.file_descr list -> float -> Unix.file_descr list * Unix.file_descr
123       list * Unix.file_descr list
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125       Suspend the execution of the calling thread until input/output  becomes
126       possible on the given Unix file descriptors.  The arguments and results
127       have the same meaning as for Unix.select .  This function is not imple‐
128       mented yet under Win32.
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132       val wait_pid : int -> int * Unix.process_status
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135       wait_pid  p  suspends  the  execution  of  the calling thread until the
136       process specified by the process identifier p terminates.  Returns  the
137       pid  of the child caught and its termination status, as per Unix.wait .
138       This function is not implemented under MacOS.
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142       val yield : unit -> unit
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144       Re-schedule the calling thread without suspending  it.   This  function
145       can be used to give scheduling hints, telling the scheduler that now is
146       a good time to switch to other threads.
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151   Management of signals
152       Signal handling follows the POSIX thread model: signals generated by  a
153       thread  are  delivered to that thread; signals generated externally are
154       delivered to one of the threads that does not block  it.   Each  thread
155       possesses  a  set  of  blocked  signals,  which  can  be modified using
156       Thread.sigmask .  This  set  is  inherited  at  thread  creation  time.
157       Per-thread signal masks are supported only by the system thread library
158       under Unix, but not under Win32, nor by the VM thread library.
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160       val sigmask : Unix.sigprocmask_command -> int list -> int list
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163       sigmask cmd sigs changes the set of blocked  signals  for  the  calling
164       thread.   If  cmd  is SIG_SETMASK , blocked signals are set to those in
165       the list sigs .  If cmd is SIG_BLOCK , the signals in sigs are added to
166       the  set  of  blocked  signals.  If cmd is SIG_UNBLOCK , the signals in
167       sigs are removed from the set of blocked signals.  sigmask returns  the
168       set of previously blocked signals for the thread.
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172       val wait_signal : int list -> int
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175       wait_signal sigs suspends the execution of the calling thread until the
176       process receives one of the signals specified in the list  sigs  .   It
177       then  returns  the  number  of  the  signal  received.  Signal handlers
178       attached to the signals in sigs will not be invoked.  The signals  sigs
179       are expected to be blocked before calling wait_signal .
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185OCamldoc                          2020-09-01                         Thread(3)