semaphore.h

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/*
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/* sempahore.h - a nut/os implementation of semaphore functions
 *
 * 2004.05.06 Matthias Ringwald <matthias.ringwald@inf.ethz.ch>
 *
 */
/*
 * $Log$
 * Revision 1.5  2007/08/29 07:43:54  haraldkipp
 * Documentation updated and corrected.
 *
 * Revision 1.4  2005/08/02 17:46:49  haraldkipp
 * Major API documentation update.
 *
 * Revision 1.3  2004/06/02 16:43:36  olereinhardt
 * fixed bug (integer overflow) in semaphore implementation
 *
 * Revision 1.2  2004/05/18 18:38:14  drsung
 * Added $Log keyword for CVS and avoid multiple inclusion of header file.
 *
 */
 
#ifndef _SYS_SEMAPHORE_H
#define _SYS_SEMAPHORE_H

#include <compiler.h>
#include <sys/types.h>
#include <sys/thread.h>


__BEGIN_DECLS

typedef struct _SEM SEM;

struct _SEM {
    HANDLE qhp;           
    short value;          
};

extern void NutSemInit(SEM * sem, short value);
extern void NutSemWait(SEM * sem);
extern int NutSemTryWait(SEM * sem);
extern void NutSemPost(SEM * sem);
extern int NutSemDestroy(SEM * sem);

__END_DECLS

#endif /* #ifndef _SYS_SEMAPHORE_H */