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diff --git a/include/rtems/pipe.h b/include/rtems/pipe.h
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+/**
+ * @file
+ *
+ * @brief POSIX FIFO/pipe File System Support
+ *
+ * This include file defines the interface to the POSIX FIFO/pipe file system
+ * support.
+ */
+
+/*
+ * Author: Wei Shen <cquark@gmail.com>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#ifndef _RTEMS_PIPE_H
+#define _RTEMS_PIPE_H
+
+#include <rtems/libio.h>
+
+/**
+ * @defgroup FIFO_PIPE FIFO/Pipe File System Support
+ *
+ * @ingroup FileSystemTypesAndMount
+ *
+ * @brief Interface to the POSIX FIFO/Pipe File System
+ */
+/**@{*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Control block to manage each pipe */
+typedef struct pipe_control {
+ char *Buffer;
+ unsigned int Size;
+ unsigned int Start;
+ unsigned int Length;
+ unsigned int Readers;
+ unsigned int Writers;
+ unsigned int waitingReaders;
+ unsigned int waitingWriters;
+ unsigned int readerCounter; /* incremental counters */
+ unsigned int writerCounter; /* for differentiation of successive opens */
+ rtems_id Semaphore;
+ rtems_id readBarrier; /* wait queues */
+ rtems_id writeBarrier;
+#if 0
+ boolean Anonymous; /* anonymous pipe or FIFO */
+#endif
+} pipe_control_t;
+
+/**
+ * @brief Create an anonymous pipe.
+ *
+ * Called by pipe() to create an anonymous pipe.
+ */
+extern int pipe_create(
+ int filsdes[2]
+);
+
+/**
+ * @brief Release a pipe.
+ *
+ * Interface to file system close.
+ *
+ * *pipep points to pipe control structure. When the last user releases pipe,
+ * it will be set to NULL.
+ */
+extern void pipe_release(
+ pipe_control_t **pipep,
+ rtems_libio_t *iop
+);
+
+/**
+ * @brief File system open.
+ * Interface to file system open.
+ *
+ * *pipep points to pipe control structure. If called with *pipep = NULL,
+ * fifo_open will try allocating and initializing a control structure. If the
+ * call succeeds, *pipep will be set to address of new control structure.
+ */
+extern int fifo_open(
+ pipe_control_t **pipep,
+ rtems_libio_t *iop
+);
+
+/**
+ * @brief File system read.
+ *
+ * Interface to file system read.
+ */
+extern ssize_t pipe_read(
+ pipe_control_t *pipe,
+ void *buffer,
+ size_t count,
+ rtems_libio_t *iop
+);
+
+/**
+ * @brief File system write.
+ *
+ * Interface to file system write.
+ */
+extern ssize_t pipe_write(
+ pipe_control_t *pipe,
+ const void *buffer,
+ size_t count,
+ rtems_libio_t *iop
+);
+
+/**
+ * @brief File system Input/Output control.
+ *
+ * Interface to file system ioctl.
+ */
+extern int pipe_ioctl(
+ pipe_control_t *pipe,
+ ioctl_command_t cmd,
+ void *buffer,
+ rtems_libio_t *iop
+);
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif