diff options
Diffstat (limited to 'System/Posix/Semaphore.hsc')
| -rw-r--r-- | System/Posix/Semaphore.hsc | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/System/Posix/Semaphore.hsc b/System/Posix/Semaphore.hsc index cef2f36..541bbdb 100644 --- a/System/Posix/Semaphore.hsc +++ b/System/Posix/Semaphore.hsc @@ -16,8 +16,8 @@ ----------------------------------------------------------------------------- module System.Posix.Semaphore - (OpenSemFlags(..), Semaphore(), - semOpen, semUnlink, semWait, semTryWait, semThreadWait, + (OpenSemFlags(..), Semaphore(), + semOpen, semUnlink, semWait, semTryWait, semThreadWait, semPost, semGetValue) where @@ -44,14 +44,14 @@ data OpenSemFlags = OpenSemFlags { semCreate :: Bool, newtype Semaphore = Semaphore (ForeignPtr ()) --- | Open a named semaphore with the given name, flags, mode, and initial +-- | Open a named semaphore with the given name, flags, mode, and initial -- value. semOpen :: String -> OpenSemFlags -> FileMode -> Int -> IO Semaphore semOpen name flags mode value = let cflags = (if semCreate flags then #{const O_CREAT} else 0) .|. (if semExclusive flags then #{const O_EXCL} else 0) semOpen' cname = - do sem <- throwErrnoPathIfNull "semOpen" name $ + do sem <- throwErrnoPathIfNull "semOpen" name $ sem_open cname (toEnum cflags) mode (toEnum value) fptr <- newForeignPtr sem (finalize sem) return $ Semaphore fptr @@ -68,7 +68,7 @@ semUnlink name = withCAString name semUnlink' -- | Lock the semaphore, blocking until it becomes available. Since this -- is done through a system call, this will block the *entire runtime*, -- not just the current thread. If this is not the behaviour you want, --- use semThreadWait instead. +-- use semThreadWait instead. semWait :: Semaphore -> IO () semWait (Semaphore fptr) = withForeignPtr fptr semWait' where semWait' sem = throwErrnoIfMinus1Retry_ "semWait" $ @@ -81,13 +81,13 @@ semTryWait (Semaphore fptr) = withForeignPtr fptr semTrywait' where semTrywait' sem = do res <- sem_trywait sem (if res == 0 then return True else do errno <- getErrno - (if errno == eINTR + (if errno == eINTR then semTrywait' sem else if errno == eAGAIN then return False else throwErrno "semTrywait")) --- | Poll the semaphore until it is available, then lock it. Unlike +-- | Poll the semaphore until it is available, then lock it. Unlike -- semWait, this will block only the current thread rather than the -- entire process. semThreadWait :: Semaphore -> IO () |