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Updated mutex and condition varable functions.

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This commit is contained in:
Marius Vollmer 2002-10-27 20:47:31 +00:00
parent e2d820a18c
commit 57c84ccd60
1 changed files with 28 additions and 6 deletions
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34
doc/ref/scheme-scheduling.texi
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@ -334,15 +334,25 @@ Create a new mutex object.
@deffn {Scheme Procedure} lock-mutex mutex
Lock @var{mutex}. If the mutex is already locked, the calling thread
blocks until the mutex becomes available. The function returns when
the calling thread owns the lock on @var{mutex}.
the calling thread owns the lock on @var{mutex}. Locking a mutex that
a thread already owns will succeed right away and will not block the
thread. That is, Guile's mutexes are @emph{recursive}.
@end deffn
@deffn {Scheme Procedure} try-mutex mutex
Try to lock @var{mutex}. If the mutex is already locked by someone
else, return @code{#f}. Else lock the mutex and return @code{#t}.
@end deffn
@c begin (texi-doc-string "guile" "unlock-mutex")
@deffn {Scheme Procedure} unlock-mutex mutex
Unlocks @var{mutex} if the calling thread owns the lock on @var{mutex}.
Calling unlock-mutex on a mutex not owned by the current thread results
in undefined behaviour. Once a mutex has been unlocked, one thread
blocked on @var{mutex} is awakened and grabs the mutex lock.
Unlocks @var{mutex} if the calling thread owns the lock on
@var{mutex}. Calling unlock-mutex on a mutex not owned by the current
thread results in undefined behaviour. Once a mutex has been unlocked,
one thread blocked on @var{mutex} is awakened and grabs the mutex
lock. Every call to @code{lock-mutex} by this thread must be matched
with a call to @code{unlock-mutex}. Only the last call to
@code{unlock-mutex} will actually unlock the mutex.
@end deffn
@c begin (texi-doc-string "guile" "make-condition-variable")
@ -350,13 +360,25 @@ blocked on @var{mutex} is awakened and grabs the mutex lock.
@end deffn
@c begin (texi-doc-string "guile" "wait-condition-variable")
@deffn {Scheme Procedure} wait-condition-variable cond-var mutex
@deffn {Scheme Procedure} wait-condition-variable cond-var mutex [time]
Wait until @var{cond-var} has been signalled. While waiting,
@var{mutex} is atomically unlocked (as with @code{unlock-mutex}) and
is locked again when this function returns. When @var{time} is given,
it specifies a point in time where the waiting should be aborted. It
can be either a integer as returned by @code{current-time} or a pair
as returned by @code{gettimeofday}. When the waiting is aborted the
mutex is locked and @code{#f} is returned. When the condition
variable is in fact signalled, the mutex is also locked and @code{#t}
is returned.
@end deffn
@c begin (texi-doc-string "guile" "signal-condition-variable")
@deffn {Scheme Procedure} signal-condition-variable cond-var
@end deffn
@c begin (texi-doc-string "guile" "broadcast-condition-variable")
@deffn {Scheme Procedure} signal-condition-variable cond-var
@end deffn
@node Higher level thread procedures
@subsection Higher level thread procedures