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+/*
+ * -------------------------------------------------------------
+ *
+ * Module: semaphore_getvalue.c
+ *
+ * Purpose:
+ * Semaphores aren't actually part of the PThreads standard.
+ * They are defined by the POSIX Standard:
+ *
+ * POSIX 1003.1b-1993 (POSIX.1b)
+ *
+ * -------------------------------------------------------------
+ *
+ * --------------------------------------------------------------------------
+ *
+ * Pthreads-win32 - POSIX Threads Library for Win32
+ * Copyright(C) 1998 John E. Bossom
+ * Copyright(C) 1999,2002 Pthreads-win32 contributors
+ *
+ * Contact Email: rpj@ise.canberra.edu.au
+ *
+ * The current list of contributors is contained
+ * in the file CONTRIBUTORS included with the source
+ * code distribution. The list can also be seen at the
+ * following World Wide Web location:
+ * http://sources.redhat.com/pthreads-win32/contributors.html
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library in the file COPYING.LIB;
+ * if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#include "pthread.h"
+#include "semaphore.h"
+#include "implement.h"
+
+
+int
+sem_getvalue(sem_t * sem, int * sval)
+ /*
+ * ------------------------------------------------------
+ * DOCPUBLIC
+ * This function stores the current count value of the
+ * semaphore.
+ * RESULTS
+ *
+ * Return value
+ *
+ * 0 sval has been set.
+ * -1 failed, error in errno
+ *
+ * in global errno
+ *
+ * EINVAL 'sem' is not a valid semaphore,
+ * ENOSYS this function is not supported,
+ *
+ *
+ * PARAMETERS
+ *
+ * sem pointer to an instance of sem_t
+ *
+ * sval pointer to int.
+ *
+ * DESCRIPTION
+ * This function stores the current count value of the semaphore
+ * pointed to by sem in the int pointed to by sval.
+ */
+{
+ int result = 0;
+
+ if ( sem == NULL || *sem == NULL || sval == NULL )
+ {
+ result = EINVAL;
+ }
+ else
+ {
+
+#ifdef NEED_SEM
+
+ result = ENOSYS;
+
+#else
+ long value = *sval;
+
+ /* Note:
+ * The windows NT documentation says that the increment must be
+ * greater than zero, but it is set to zero here. If this works,
+ * the function will return true. If not, we can't do it this way
+ * so flag it as not implemented.
+ */
+
+ if ( ReleaseSemaphore( (*sem)->sem, 0L, &value) )
+ {
+ *sval = value;
+ }
+ else
+ {
+ result = ENOSYS;
+ }
+
+#endif
+ }
+
+
+ if ( result != 0 )
+ {
+ errno = result;
+ return -1;
+ }
+
+ return 0;
+
+} /* sem_getvalue */